1

base

play
noun \ˈbās\

Definition of base

plural

bases

play \ˈbā-səz\
  1. 1a 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)b :  the bottom of something considered as its support :  foundation the base of the mountain the lamp's heavy basec mathematics (1) :  a side or face (see 1face 5a(5)) of a geometrical figure from which an altitude (see altitude 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 based 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

  2. 2a :  a main ingredient paint having a latex baseb :  a supporting or carrying ingredient (as of a medicine)

  3. 3a :  the fundamental part of something :  groundwork, basis the book's theoretical base her broad base of knowledgeb :  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 McCainc Marxism :  the economic factors on which all legal, social, and political relations are formed

  4. 4 heraldry :  the lower part of a heraldic field (see 1field 3c)

  5. 5a :  the starting point or line for an action or undertaking plans to make this city his base of operation — J. A. Loftusb :  a baseline in surveyingc :  a center or area of operations The company has its base in London.: such as (1) :  the place from which a military force draws supplies (2) :  a place where military operations begin (3) :  a permanent military installation a naval base The troops were ordered back to base.d mathematics (1) :  a number (such as 5 in 56.44 or 57) that is raised to a power (see 1power 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 1place 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.e linguistics :  root 6 “Leave” is the base of the verb “left.”

  6. 6a in various games :  the starting place or goalb :  any one of the four stations at the corners of a baseball or softball infield allowing the batter to reach basec :  a point to be considered His opening remarks touched every base.

  7. 7 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 acidb :  any of the five purine or pyrimidine bases of DNA and RNA that include cytosine, guanine, adenine, thymine, and uracil

  8. 8 finance :  a price level at which a security (see security 3) previously declining in price resists further decline

  9. 9 linguistics :  the part of a transformational grammar that consists of rules and a lexicon and generates the deep structures of a language

  10. 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 1gate 5b

based

play \ˈbāst\ adjective

baseless

play \ˈbā-sləs\ adjective

cover all the bases

or less commonly

cover every base

or

have (all) one's bases covered

  1. :  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. 1 :  wrong, mistaken Estimates were way off base.

  2. 2 :  unawares caught off base by the charges

touch all the bases

or less commonly

touch every base

  1. 1 :  to mention every subject that needs to be considered a speech that touches all the bases

  2. 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

Examples of base in a Sentence

  1. the firm belief that complete trust between husband and wife is the base of any successful marriage

  2. the army's base of attack was kept top secret until the battle began

Illustration of base

Origin and Etymology of base

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


First Known Use: 14th century


2

base

verb

Definition of base

based

;

basing

  1. transitive verb
  2. 1 :  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

  3. 2 :  to find a foundation or basis for :  to find a base (see 1base 3a) for —usually used with on or upon base an opinion on faulty information a story based upon real-life events

Examples of base in a Sentence

  1. They are going to base their new company in Seattle.

  2. The company has based itself in London.

  3. Our tour group based itself in a hotel in the heart of the city.

Origin and Etymology of base

verbal derivative of 1base


First Known Use: 1587


3

base

adjective

Definition of base

  1. 1 archaic :  of little height … the cedar stoops not to the base shrub's foot … — Shakespeare

  2. 2 obsolete :  low in place or position … fall to the base earth from the firmament! — Shakespeare

  3. 3 obsolete :  bass

  4. 4 archaic :  baseborn base in kind and born to be a slave. — William Cowper

  5. 5 feudalism a :  resembling a villein :  servile a base tenantb :  held by villenage base tenure

  6. 6a :  being of comparatively low value and having relatively inferior properties (such as lack of resistance to corrosion) a base metal such as iron — compare nobleb :  containing a larger than usual proportion of base metals base silver denarii

  7. 7a :  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 instinctsb :  lacking higher values :  degrading a drab base way of life

basely

adverb

baseness

noun

Examples of base in a Sentence

  1. Iron is a base metal.

  2. a base and sneaky act that is a clear violation of international law

Origin and Etymology of base

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


First Known Use: 14th century

Synonym Discussion of 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

BASE Defined for English Language Learners

1

base

play
noun \ˈbās\

Definition of base for English Language Learners

  • : the bottom or lowest part of something : the part on which something rests or is supported

  • : something (such as a group of people or things) that provides support for a place, business, etc.

  • : a main ingredient to which other things are added to make something

2

base

verb

Definition of base for English Language Learners

  • : to have a particular place as the main place where a person works or lives or where a business operates

3

base

adjective

Definition of base for English Language Learners

  • : not honest or good

  • of a metal : having low quality and value


BASE Defined for Kids

1

base

play
noun \ˈbās\

Definition of base for Students

  1. 1 :  a thing or a part on which something rests :  bottom, foundation the base of a statue the base of the mountain

  2. 2 :  a starting place or goal in various games

  3. 3 :  any of the four stations a runner in baseball must touch in order to score

  4. 4 :  the main place or starting place of an action or operation The company's base is in New York.

  5. 5 :  a place where a military force keeps its supplies or from which it starts its operations an air force base

  6. 6 :  a line or surface of a geometric figure upon which an altitude is or is thought to be constructed base of a triangle

  7. 7 :  the main substance in a mixture

  8. 8 :  a number with reference to which a system of numbers is constructed

  9. 9 :  a chemical substance (as lime or ammonia) that reacts with an acid to form a salt and turns red litmus paper blue


2

base

play
verb

Definition of base for Students

based

;

basing

  1. :  to use as a main place of operation or action The company is based in Ohio.

base on

or

base upon

  1. :  to make or form from a starting point It's based on a true story.


3

base

play
adjective

Definition of base for Students

baser

;

basest

  1. 1 :  of low value and not very good in some ways base metals

  2. 2 :  not honorable “I'll appeal to his baser instincts, of which he has plenty.” — E. B. White, Charlotte's Web


Medical Dictionary

base

play
noun \ˈbās\

Medical Definition of base

plural

bases

\ˈbā-səz\play
  1. 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. 2a:  the usually inactive ingredient of a preparation serving as the vehicle for the active medicinal preparation the fatty base of an ointmentb:  the chief active ingredient of a preparation—called also basis

  3. 3a:  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 are substances able to give up an unshared pair of electrons to an acid—compare alkalib:  any of the five purine or pyrimidine bases of DNA and RNA that include cytosine, guanine, adenine, thymine, and uracil

  4. 4:  freebase

based

\ˈbāst\play adjective


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