n.

1. any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water;
   alkali
   
   • bases include oxides and hydroxides of metals and ammonia
2. installation from which a military force initiates operations;
   base of operations
   
   • the attack wiped out our forward bases
3. lowest support of a structure;
   foundation, fundament, foot, groundwork, substructure, understructure
   
   • it was built on a base of solid rock
   • he stood at the foot of the tower
4. place that runner must touch before scoring;
   bag
   
   • 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;
   radix
   
   • 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;
   floor
   
   • the government established a wage floor
9. the fundamental assumptions from which something is begun or developed or calculated or explained;
   basis, foundation, fundament, groundwork, cornerstone
   
   • the whole argument rested on a basis of conjecture
10. a support or foundation;
    pedestal, stand
    
    • 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;
    basis
    
    • the basis of this drink is orange juice
13. the place where you are stationed and from which missions start and end;
    home
14. a terrorist network intensely opposed to the United States that dispenses money and logistical support and training to a wide variety of radical Islamic terrorist groups; has cells in more than 50 countries;
    al-Qaeda, Qaeda, al-Qa'ida, al-Qaida, Base
15. (linguistics) the form of a word after all affixes are removed;
    root, root word, stem, theme, radical
    
    • thematic vowels are part of the stem
16. the stock of basic facilities and capital equipment needed for the functioning of a country or area;
    infrastructure
    
    • the industrial base of Japan
17. the principal ingredient of a mixture
    
    • glycerinated gelatin is used as a base for many ointments
    • he told the painter that he wanted a yellow base with just a hint of green
    • everything she cooked seemed to have rice as the base
18. a flat bottom on which something is intended to sit
    
    • a tub should sit on its own base
19. (electronics) the part of a transistor that separates the emitter from the collector

v.

1. use as a basis for; found on;
   establish, ground, found
   
   • base a claim on some observation
2. use (purified cocaine) by burning it and inhaling the fumes;
   free-base
3. assign to a station;
   station, post, send, place

adj.

1. serving as or forming a base;
   basal
   
   • the painter applied a base coat followed by two finishing coats
2. (used of metals) consisting of or alloyed with inferior metal
   
   • base coins of aluminum
   • a base metal
3. of low birth or station (`base' is archaic in this sense);
   baseborn, humble, lowly
   
   • baseborn wretches with dirty faces
   • of humble (or lowly) birth
4. not adhering to ethical or moral principles;
   dishonorable, dishonourable, immoral, unethical
   
   • base and unpatriotic motives
   • a base, degrading way of life
   • cheating is dishonorable
   • they considered colonialism immoral
   • unethical practices in handling public funds
5. having or showing an ignoble lack of honor or morality;
   mean, meanspirited
   
   • that liberal obedience without which your army would be a base rabble"- Edmund Burke; "taking a mean advantage
   • chok'd with ambition of the meaner sort"- Shakespeare; "something essentially vulgar and meanspirited in politics
6. illegitimate;
   baseborn
7. debased; not genuine
   
   • an attempt to eliminate the base coinage