1.any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water;

bases include oxides and hydroxides of metals and ammonia

2.installation from which a military force initiates operations;

the attack wiped out our forward bases

3.lowest support of a structure;

it was built on a base of solid rock

4.place that runner must touch before scoring;

he scrambled to get back to the bag

5.(numeration system) the positive integer that is equivalent to one in the next higher counting place;

10 is the radix of the decimal system

6.the bottom or lowest part;

the base of the mountain

7.(anatomy) the part of an organ nearest its point of attachment;

the base of the skull

8.a lower limit;

the government established a wage floor

9.the fundamental assumptions from which something is begun or developed or calculated or explained;

the whole argument rested on a basis of conjecture

10. a support or foundation;

the base of the lamp

11. the bottom side of a geometric figure from which the altitude can be constructed;

the base of the triangle

12. the most important or necessary part of something;

the basis of this drink is orange juice

13. the place where you are stationed and from which missions start and end

14. (linguistics) the form of a word after all affixes are removed;

thematic vowels are part of the stem

15. the stock of basic facilities and capital equipment needed for the functioning of a country or area;

the industrial base of Japan

16. the principal ingredient of a mixture;

glycerinated gelatin is used as a base for many ointments

17. a flat bottom on which something is intended to sit;

a tub should sit on its own base

18. (electronics) the part of a transistor that separates the emitter from the collector

19.serving as or forming a base;

the painter applied a base coat followed by two finishing coats

20.(used of metals) consisting of or alloyed with inferior metal;

base coins of aluminum

21.of low birth or station (`base' is archaic in this sense);

baseborn wretches with dirty faces

22.not adhering to ethical or moral principles;

base and unpatriotic motives

23.having or showing an ignoble lack of honor or morality;

that liberal obedience without which your army would be a base rabble- Edmund Burke

24.illegitimate

25.debased; not genuine;

an attempt to eliminate the base coinage