Definition of base
(Entry 1 of 4)
1a
: 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)
(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
2a
: 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
3a
: 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 basethe band's fan baseBut 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
4a
: the starting point or line for an action or undertaking
plans to make this city his base of operation— J. A. Loftus
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
(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.
5a
: 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, 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
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
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
cover all the bases
or less commonly cover every base
or have (all) one's bases covered
off base
touch all the bases
or less commonly touch every base
: 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
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
base
verb
based; basing
Definition of base (Entry 2 of 4)
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 informationa 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
adjective (1)Definition of base (Entry 3 of 4)
1a
: lacking or indicating the lack of higher qualities of mind or spirit : ignoble
seemed a base betrayal of idealism— L. M. Sears appealing to a person's baser instincts
b
: lacking higher values : degrading
a drab base way of life
2a
: 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
4
archaic
: of little height
… the cedar stoops not to the base shrub's foot …— Shakespeare
6
obsolete
: low in place or position
… fall to the base earth from the firmament!— Shakespeare
base
adjective (2)Definition of base (Entry 4 of 4)
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
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Merriam-Webster unabridged
Share base
Time Traveler for base
The first known use of base was in the 14th century
See more words from the same century