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¹base

noun \ˈbās\

: 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

plural bas·es \ˈbā-səz\

Full Definition of BASE

a (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

b : the bottom of something considered as its support : foundation

c (1) : a side or face of a geometrical figure from which an altitude can be constructed; especially : one on which the figure stands (2) : the length of a base

d : that part of a bodily organ by which it is attached to another more central structure of the organism

a : a main ingredient <paint having a latex base>

b : a supporting or carrying ingredient (as of a medicine)

a : the fundamental part of something : groundwork, basis

b : the economic factors on which in Marxist theory all legal, social, and political relations are formed

: the lower part of a heraldic field

a : the starting point or line for an action or undertaking

b : a baseline in surveying

c : a center or area of operations: as (1) : the place from which a military force draws supplies (2) : a place where military operations begin (3) : a permanent military installation

d (1) : a number (as 5 in 5^6.44 or 5⁷) that is raised to a power; 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 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 : root 6

a : the starting place or goal in various games

b : any one of the four stations at the corners of a baseball infield

c : a point to be considered <his opening remarks touched every base>

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

: a price level at which a security previously declining in price resists further decline

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

— based \ˈbāst\ adjective

— base·less \ˈbā-sləs\ adjective

— off base

: wrong, mistaken <estimates were way off base>

: unawares <caught off base by the charges>

See base defined for English-language learners

See base defined for kids

Illustration of BASE

Origin of BASE

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

First Known Use: 13th century

Related to BASE

Synonyms: basis, bedrock, bottom, cornerstone, footing, foundation, ground, groundwork, keystone, root, underpinning, warp, warp and woof

Antonyms: head, top, vertex

Rhymes with BASE

ace, bass, brace, case, chase, dace, face, grace, lace, mace, Mace, Naas, pace, place, plaice, prase, race, res, space, Thrace, trace, vase, Wace

²base

verb

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

basedbas·ing

Full Definition of BASE

transitive verb

: to make, form, or serve as a base for

: to find a base or basis for —usually used with on or upon

See base defined for English-language learners

First Known Use of BASE

1587

Related to BASE

Synonyms: ground, hang, predicate, rest

³base

adjective

: not honest or good

of a metal : having low quality and value

Full Definition of BASE

archaic : of little height

obsolete : low in place or position

obsolete : bass

archaic : baseborn

a : resembling a villein : servile <a base tenant>

b : held by villenage <base tenure>

a : being of comparatively low value and having relatively inferior properties (as lack of resistance to corrosion) <a base metal such as iron> — compare noble

b : containing a larger than usual proportion of base metals <base silver denarii>

a : lacking or indicating the lack of higher qualities of mind or spirit : ignoble

b : lacking higher values : degrading <a drab base way of life>

— base·ly adverb

— base·ness noun

See base defined for English-language learners

Origin of BASE

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

First Known Use: 14th century

Related to BASE

Synonyms: ignoble, contemptible, currish, despicable, detestable, dirty, dishonorable, execrable, ignominious, low, low-down, low-minded, mean, nasty, paltry, snide, sordid, vile, wretched

Antonyms: high, high-minded, honorable, lofty, noble, straight, upright, venerable, virtuous

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 Kids

¹base

noun \ˈbās\

Definition of BASE for Kids

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

: a starting place or goal in various games

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

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

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

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

: the main substance in a mixture

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

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

²base

verb

basedbas·ing

Definition of BASE for Kids

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

— base on or base upon

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

³base

adjective

bas·erbas·est

Definition of BASE for Kids

: of low value and not very good in some ways <base metals>

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

Medical Dictionary

base

noun \ˈbās\

plural bas·es \ˈbā-səz\

Medical Definition of BASE

: 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>

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

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 are substances 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

: freebase

—based \ˈbāst\ adjective