noun: The lowest or bottom part: the base of a cliff; the base of a lamp.
noun: Biology The part of a plant or animal organ that is nearest to its point of attachment.
noun: Biology The point of attachment of such an organ.
noun: A supporting part or layer; a foundation: a skyscraper built on a base of solid rock.
noun: A basic or underlying element; infrastructure: the nation's industrial base.
noun: The fundamental principle or underlying concept of a system or theory; a basis.
noun: A fundamental ingredient; a chief constituent: a paint with an oil base.
noun: The fact, observation, or premise from which a reasoning process is begun.
noun: Games A starting point, safety area, or goal.
noun: Baseball Any one of the four corners of an infield, marked by a bag or plate, that must be touched by a runner before a run can be scored.
noun: A center of organization, supply, or activity; a headquarters.
noun: A fortified center of operations.
noun: A supply center for a large force of military personnel.
noun: A facial cosmetic used to even out the complexion or provide a surface for other makeup; a foundation.
noun: Architecture The lowest part of a structure, such as a wall, considered as a separate unit: the base of a column.
noun: Heraldry The lower part of a shield.
noun: Linguistics A morpheme or morphemes regarded as a form to which affixes or other bases may be added.
noun: Mathematics The side or face of a geometric figure to which an altitude is or is thought to be drawn.
noun: Mathematics The number that is raised to various powers to generate the principal counting units of a number system. The base of the decimal system, for example, is 10.
noun: Mathematics The number raised to the logarithm of a designated number in order to produce that designated number; the number at which a chosen logarithmic scale has the value 1.
noun: A line used as a reference for measurement or computations.
noun: Chemistry Any of a class of compounds whose aqueous solutions are characterized by a bitter taste, a slippery feel, the ability to turn litmus blue, and the ability to react with acids to form salts.
noun: Chemistry A substance that yields hydroxyl ions when dissolved in water.
noun: Chemistry A substance that can act as a proton acceptor.
noun: Chemistry A substance that can donate a pair of electrons to form a covalent bond.
noun: Electronics The region in a transistor between the emitter and the collector.
noun: Electronics The electrode attached to this region.
noun: One of the nitrogen-containing purines (adenine and guanine) or pyrimidines (cytosine, thymine, and uracil) that occurs attached to the sugar component of DNA or RNA.
adjective: Forming or serving as a base: a base layer of soil.
adjective: Situated at or near the base or bottom: a base camp for the mountain climbers.
adjective: Chemistry Of, relating to, or containing a base.
verb-transitive: To form or provide a base for: based the new company in Portland.
verb-transitive: To find a basis for; establish: based her conclusions on the report; a film based on a best-selling novel.
verb-transitive: To assign to a base; station: troops based in the Middle East.
idiom: off base Badly mistaken.
adjective: Having or showing a contemptible, mean-spirited, or selfish lack of human decency. See Synonyms at mean2.
adjective: Devoid of high values or ethics: a base, degrading way of life.
adjective: Inferior in value or quality.
adjective: Containing inferior substances: a base metal.
adjective: Archaic Of low birth, rank, or position.