from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Having or showing a lack of decency; contemptible, mean-spirited, or selfish.
  • adjective Being a metal that is of little value.
  • adjective Containing such metals.
  • adjective Archaic Of low birth, rank, or position.
  • adjective Obsolete Short in stature.
  • noun A bass singer or voice.
  • noun The lowest or bottom part.
  • noun The part of a plant or animal organ that is nearest to its point of attachment.
  • noun The point of attachment of such an organ.
  • noun A supporting part or layer; a foundation.
  • noun A basic or underlying element; infrastructure.
  • noun The fundamental principle or underlying concept of a system or theory; a basis.
  • noun A fundamental ingredient; a chief constituent.
  • 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 The portion of a social organization, especially a political party, consisting of the most dedicated or motivated members.
  • 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.
  • 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 The side or face of a geometric figure to which an altitude is or is thought to be drawn.
  • noun 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 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 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 A substance that yields hydroxide ions when dissolved in water.
  • noun A substance that can act as a proton acceptor.
  • noun A substance that can donate a pair of electrons to form a covalent bond.
  • noun The region in a transistor between the emitter and the collector.
  • noun 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.
  • adjective Situated at or near the base or bottom.
  • adjective Chemistry Of, relating to, or containing a base.
  • transitive verb To form or provide a base for.
  • transitive verb To find a basis for; establish.
  • transitive verb To assign to a base; station.


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English bas, low, from Old French, from Medieval Latin bassus.]

from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English, from Old French, from Latin basis, from Greek; see gwā- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Old French base, from Latin basis, from Ancient Greek βάσις (basis).

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Old French bas, from Late Latin bassus ("low").


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  • (n): in photography and cinematography, the clear perforated strip of film upon which the light-sensitive emulsion layer is affixed.

    January 18, 2009

  • xkcd, "The Base Metaphor Explained"

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