cold feet(n = noun.feeling) - timidity that prevents the continuation of a course of action; "I was going to tell him but I got cold feet"
is a kind of timidity, timidness, timorousness

N  cowardice, pusillanimity, cowardliness, timidity, effeminacy, poltroonery, baseness, dastardness, dastardy, abject fear, funk, Dutch courage, fear, white feather, faint heart, cold feet, yellow streak, coward, poltroon, dastard, sneak, recreant, shy cock, dunghill cock, coistril, milksop, white liver, lily liver, nidget, one that cannot say 'boo' to a goose, slink, Bob Acres, Jerry Sneak, alarmist, terrorist, pessimist, runagate, coward, cowardly, fearful, shy, timid, timorous, skittish, poor- spirited, spiritless, soft, effeminate, weak-minded, infirm of purpose, weak-hearted, fainthearted, chickenhearted, henhearted, lilyhearted, pigeon-hearted, white- livered, lily-livered, milk-livered, milksop, smock-faced, unable to say 'boo' to a goose, dastard, dastardly, base, craven, sneaking, dunghill, recreant, unwarlike, unsoldier-like, in face a lion but in heart a deer, unmanned, frightened, Int, sauve qui peut!, every man for himself!, devil take the hindmost!, ante tubam trepidat, one's courage oozing out, degeneres animos timor arguit.

blow hot and cold, calves' feet, cat's feet, catch cold, cold, cold blooded, cold cash, cold cereal, cold chisel, cold comfort, cold cream, cold cuts, cold duck, cold fish, cold frame, cold front, cold fusion, cold gangrene, cold medicine, cold rubber, cold shoulder, cold snap, cold sober, cold sore, cold spell, cold storage, cold stuffed tomato, cold sweat, cold turkey, cold type, cold war, cold water, cold wave, cold weather, cold work, common cold, crow's feet, drag one's feet, feet, head cold, ice cold, in cold blood, itchy feet, knock cold, out cold, pigs' feet, pour cold water on, stone cold, throw cold water on