base

Concise Oxford English Dictionary © 2008 Oxford University Press:
base1

▶noun

• 1 the lowest part of something, especially the part on which it rests or is supported.

  ■ Architecture the part of a column between the shaft and pedestal or pavement.

  ■ Botany & Zoology the end at which a part or organ is attached to the trunk or main part.

• 2 a conceptual structure or entity on which something draws or depends: the town's economic base collapsed.

  ■ a foundation or starting point.

• 3 a person's main place of work or residence.

  ■ a centre of operations for military or other activity.

• 4 a main element or ingredient to which other things are added.

  ■ a substance into which a pigment is mixed to form paint.

• 5 Chemistry a substance capable of reacting with an acid to form a salt and water, or of accepting or neutralizing hydrogen ions.

• 6 Electronics the middle part of a bipolar transistor, separating the emitter from the collector.

• 7 Linguistics the root or stem of a word or a derivative.

  ■ the uninflected form of a verb.

• 8 Mathematics a number used as the basis of a numeration scale.

  ■ a number in terms of which other numbers are expressed as logarithms.

• 9 Baseball one of the four stations that must be reached in turn to score a run.

▶verb

• 1 (base something on) use something as the foundation for: the film is based on a novel.

• 2 use a place as a centre of operations.

– phrases
get to first base informal, chiefly N. Amer. achieve the first step towards one's objective.
off base informal mistaken.
touch base informal briefly make or renew contact.

– derivatives
-based adjective.

– origin ME: from OFr., from L. basis ‘base, pedestal’, from Gk.

Concise Oxford English Dictionary © 2008 Oxford University Press:
base2

▶adjective

• 1 without moral principles; ignoble.

• 2 archaic denoting or befitting a person of low social class.

• 3 (of coins or other articles) not made of precious metal.

– derivatives
basely adverb,
baseness noun.

– origin ME (in the sense ‘low, short’): from OFr. bas, from med. L. bassus ‘short’ (found in classical L. as a cognomen).