base

1 of 4

noun

plural bases ˈbā-səz How to pronounce base (audio)
1
a
: the bottom of something considered as its support : foundation
the base of the mountain
the lamp's heavy base
b
biology : that part of a bodily organ by which it is attached to another more central structure of the organism
the base of the thumb
c architecture
(1)
: the lower part of a wall, pier, or column considered as a separate architectural feature
(2)
: the lower part of a complete architectural design (as of a monument)
d mathematics
(1)
: a side or face (see face entry 1 sense 5a(5)) of a geometrical figure from which an altitude (see altitude sense 1c(1)) can be constructed
especially : a side or face on which the figure stands
the base of a triangle
(2)
: the length of a base
determining the triangle's base
2
a
: a main ingredient
paint having a latex base
b
: a supporting or carrying ingredient (as of a medicine)
c
: a first or bottom layer of something on which other elements are added
Overnight, Utah's famous snow has freshly blanketed both runs, adding to a solid base of three feet …Abby Carroll
3
a
: the fundamental part of something : groundwork, basis
the book's theoretical base
her broad base of knowledge
b
: something (as a group of people) that reliably provides support (such as for a business or political candidate)
usually singular
efforts to expand their customer base
the band's fan base
But I do believe that that's a very sore point with many Democrats and could be used to energize their base.John McCain
c
Marxism : the economic factors on which all legal, social, and political relations are formed
4
a
: the starting point or line for an action or undertaking
plans to make this city his base of operationJ. A. Loftus
b
c
: a center or area of operations
The company has its base in London.
: such as
(1)
: a permanent military installation
a naval base
The troops were ordered back to base.
(2)
: the place from which a military force draws supplies
(3)
: a place where military operations begin
d
linguistics : root sense 6
"Leave" is the base of the verb "left."
e mathematics
(1)
: a number (such as 5 in 56.44 or 57) that is raised to a power (see power entry 1 sense 5a)
especially : the number that when raised to a power equal to the logarithm of a number yields the number itself
The logarithm of 100 to the base 10 is 2 since 102 = 100.
(2)
: a number equal to the number of units in a given digit's place (see place entry 1 sense 8) that for a given system of writing numbers is required to give the numeral 1 in the next higher place
The decimal system uses a base of 10.
also : such a system of writing numbers using an indicated base
Convert from base 10 to base 2.
(3)
: a number that is multiplied by a rate or of which a percentage or fraction is calculated
To find the interest on $90 at 10 percent multiply the base 90 by .10.
5
a
: any one of the four stations at the corners of a baseball or softball infield
allowing the batter to reach base
b
in various games : the starting place or goal
c
: a point to be considered
His opening remarks touched every base.
6
chemistry
a
: any of various typically water-soluble and bitter tasting compounds that in solution have a pH greater than 7, are capable of reacting with an acid to form a salt, turn litmus blue, and are molecules or ions able to take up a proton from an acid or able to give up an unshared pair of electrons to an acid
Baking soda is a common household base.
b
: any of the five purine or pyrimidine bases of DNA and RNA that include cytosine, guanine, adenine, thymine, and uracil
7
finance : a price level at which a security (see security sense 3) previously declining in price resists further decline
8
heraldry : the lower part of a heraldic field (see field entry 1 sense 3c)
9
linguistics : the part of a transformational grammar that consists of rules and a lexicon and generates the deep structures of a language
10
: an electrode that modulates the current flowing through a bipolar junction transistor according to the voltage applied to the electrode
This gate, which is called a grid in a tube and a base in a transistor, enables a small "controlling" voltage to turn on and off a much larger voltage between the cathode and the anode.Thom Hartmann
compare gate entry 1 sense 5b
baseless adjective

Illustration of base

Illustration of base
  • 1 upper torus
  • 2 scotia
  • 3 lower torus
  • 4 plinth
  • 5 shaft
  • 6 fillets

base

2 of 4

verb

based; basing

transitive verb

1
: to find a foundation or basis for : to find a base (see base entry 1 sense 3a) for
usually used with on or upon
base an opinion on faulty information
a story based upon real-life events
2
: to make, form, or serve as a base for
… great roots based the tree columns …George Macdonald
the company is based in London
clients who are based out of their homes

base

3 of 4

adjective (1)

1
a
: lacking or indicating the lack of higher qualities of mind or spirit : ignoble
seemed a base betrayal of idealismL. M. Sears
appealing to a person's baser instincts
b
: lacking higher values : degrading
a drab base way of life
2
a
: being of comparatively low value and having relatively inferior properties (such as lack of resistance to corrosion)
a base metal such as iron
compare noble entry 1
b
: containing a larger than usual proportion of base metals
base silver denarii
3
feudalism
a
: resembling a villein : servile
a base tenant
b
: held by villenage
base tenure
4
archaic : of little height
… the cedar stoops not to the base shrub's foot …Shakespeare
5
archaic : baseborn
base in kind and born to be a slave.William Cowper
6
obsolete : low in place or position
… fall to the base earth from the firmament!Shakespeare
7
obsolete : bass
basely adverb
baseness noun

base

4 of 4

adjective (2)

1
: constituting or serving as a base
This situation is frequently encountered by seaplane pilots in northern Canada who must fly over lakes and tundra to a base camp located on a river.Alan Lopez
2
: of the simplest or most basic design or form : having the form of something before upgrades or customization
This GTO's 350-hp, 5.7-liter V8 is the same that's used in the base Corvette, and it produces the power and throaty exhaust sound of a classic muscle car.Consumer Reports
Phrases
cover all the bases or less commonly cover every base or have (all) one's bases covered
: to do or include everything that needs to be done or included : to fulfill all requirements or necessities
The well rounded menu covers all the bases—pork or duck breast and always a grilled chicken with complementary sauces and relishes …Caroline Bates
In other words, we need to cover every base. Too often, something is remembered at the last minute and we find ourselves waiting for the stores to open on sale day so we can purchase a much-needed item.Sue Story
In your e-mail, let the company know that, for their convenience, you're e-mailing the resume and letter, but that the original documents will arrive by postal service. This way you've got all your bases covered.Peter Post
off base
1
: wrong, mistaken
Estimates were way off base.
2
: unawares
caught off base by the charges
touch all the bases or less commonly touch every base
1
: to mention every subject that needs to be considered
a speech that touches all the bases
2
: to do or include everything that needs to be done or included : to fulfill all requirements or necessities
need to touch all the bases when applying for a mortgage
The owner of the Utah Stars is in Salt Lake City, working 24 hours a day in an effort to touch every base to keep his club in Utah's capital city.Dan Pattison
Choose the Right Synonym for base

base, low, vile mean deserving of contempt because of the absence of higher values.

base stresses the ignoble and may suggest cruelty, treachery, greed, or grossness.

base motives

low may connote crafty cunning, vulgarity, or immorality and regularly implies an outraging of one's sense of decency or propriety.

refused to listen to such low talk

vile, the strongest of these words, tends to suggest disgusting depravity or filth.

a vile remark

Examples of base in a Sentence

Noun their base obedience to every unprincipled action ordered by their leader the army's base of attack was kept top secret until the battle began Verb They are going to base their new company in Seattle. The company has based itself in London. Our tour group based itself in a hotel in the heart of the city. Adjective (1) Iron is a base metal. a base and sneaky act that is a clear violation of international law
Recent Examples on the Web
Noun
Full Artificial Christmas Tree The 59-inch base helps this 7.5-foot tree look full and lifelike. Jessica Comstock, Better Homes & Gardens, 7 Oct. 2024 Cottage Cheese Breakfast Bowl Cottage cheese is a great base for toppings. Johna Burdeos, Health, 7 Oct. 2024
Verb
The problem is that, according to several studies, 45% to 50% of people lack the ability to detect such patterns, which may lead them to make important decisions based on entirely false premises. Luis E. Romero, Forbes, 8 Oct. 2024 But regardless of experience level, these producers — selected based on their histories on the Billboard Hot 100 and Billboard’s Hot 100 producers chart, along with placements on other charts — are helping to define music’s future. Rebecca Milzoff, Billboard, 8 Oct. 2024
Adjective
Chicken broth: Provides the base liquid for the soup. Julia Levy, Southern Living, 8 Oct. 2024 The standard edition, which goes for $39.99, includes the base expansion, while the deluxe edition, which goes for $59.99, includes the base expansion and additional armors, skins, animal companions and more. Rudie Obias, Variety, 8 Oct. 2024 See all Example Sentences for base 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'base.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

Middle English, from Anglo-French, from Latin basis, from Greek, step, base, from bainein to go — more at come

Verb

verbal derivative of base entry 1

Adjective (1)

Middle English bas, from Anglo-French, from Late Latin bassus fat, short, low

First Known Use

Noun

14th century, in the meaning defined at sense 1c(1)

Verb

1587, in the meaning defined at sense 2

Adjective (1)

14th century, in the meaning defined at sense 4

Adjective (2)

1734, in the meaning defined at sense 1

Time Traveler
The first known use of base was in the 14th century

Dictionary Entries Near base

Cite this Entry

“Base.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/base. Accessed 13 Oct. 2024.

Kids Definition

base

1 of 3 noun
plural bases ˈbā-səz How to pronounce base (audio)
1
a
: a thing or part on which something rests : bottom, foundation
the base of a lamp
b
: the part of a plant or animal structure by which it is attached to another more central structure
the base of the thumb
c
: one of the lines or flat surfaces of a geometric figure from which an altitude is or can be constructed
bases of a trapezoid
especially : one on which the figure stands
base of a triangle
2
: a main ingredient
paint having a water base
3
: a fundamental part : basis
4
a
: the place from which a start is made
b
: a line in a survey that is used to calculate distances or positions
c
: a place where a military force keeps its supplies or from which it starts its operations
naval base
air base
d
: a number equal to the number of units that would be equivalent to one in the next higher place in a given number system
in base 10 it takes 10 ones in the units place to equal a one in the tens place
also : a system of writing numbers using a given base
convert base 10 to base 2
5
a
: the starting place or goal in various games
b
: any of the four stations a runner in baseball must touch in order to score
6
: any of various compounds that react with an acid to form a salt, have a bitter taste, and turn red litmus paper blue
7
: a number that is multiplied by a rate or of which a percentage or fraction is calculated
to find the interest on $90 at 10% multiply the base 90 by .10
based adjective
baseless adjective

base

2 of 3 verb
based; basing
1
: to make, form, or serve as a base for
2
: to use as a base or basis for : establish

base

3 of 3 adjective
1
a
: being of low value and having less desirable properties when compared with something else
a base metal such as iron
b
: containing more than the usual amount of base metals
2
: not honorable or moral : mean
base conduct
basely adverb
baseness noun

Medical Definition

base

noun
plural bases ˈbā-səz How to pronounce base (audio)
1
: that portion of a bodily organ or part by which it is attached to another more central structure of the organism
the base of the thumb
2
a
: the usually inactive ingredient of a preparation serving as the vehicle for the active medicinal preparation
the fatty base of an ointment
b
: the chief active ingredient of a preparation

called also basis

3
a
: any of various typically water-soluble and bitter tasting compounds that in solution have a pH greater than 7, are capable of reacting with an acid to form a salt, and are molecules or ions able to take up a proton from an acid or able to give up an unshared pair of electrons to an acid compare alkali
b
: any of the five purine or pyrimidine bases of DNA and RNA that include cytosine, guanine, adenine, thymine, and uracil
4
based adjective

More from Merriam-Webster on base

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