big, large

Each of these words refers to quantity and size and in most speaking and writing situations can be used interchangeably (a big building, a large building). Large, however, carries a meaning of immensity or importance not conveyed by big (a man of large vision rather than a man of big vision). Big carries additional meanings of generosity or kindness, as in the phrases "a big heart" and "a big man in every way." Although distinctions in meaning have broken down somewhat and although big is more often used than large, your language sense will tell you to use big when you mean either size or importance and large when there is an added suggestion of scope or range: "a big liar," not "a large liar," and "a man of large outlook" rather than "a man of big outlook." But remember that big is an overworked term and that it appears in numerous trite, slangy expressions that should be avoided in all but informal conversation: "big on" ("enthusiastic about"); "talk big" ("to speak boastfully"); "go over big" ("to be successful"); "big cheese," "big shot" ("important person"); "big eye" ("invitation," "summons"); "big idea" ("unsolicited or objectionable proposal or plan"); "big mouth" ("loud person"); "big talk" ("exaggeration"); "big time" ("enjoyable time," "high level"); "big wheel," "big wig" ("influential person"); "big head" ("conceit," "egotism"); "big house" ("penitentiary"). It's possible that you use big in even more expressions than those listed here. Be big and avoid them all.