adj. 1 slim, slender, lean, spare, slight, lanky, spindly, skinny, thin as a rail or reed or rake, wispy, twiggy, skeletal, gaunt, gangling, bony, emaciated, cadaverous, meagre, scrawny, all skin and bones, scraggy, undernourished, underfed, underweight, undersized, puny, sparse, hollow-cheeked, (half-)starved, pinched, withered, shrunken, shrivelled (up) Douglas is quite thin as a result of his illness 2 sparse, unsubstantial, poor, scant, insufficient, inadequate, slight, worthless, unimportant, deficient, skimpy, unplentiful, paltry, piddling This year's harvest has been very thin 3 attenuated, threadlike, stringlike, pencil-thin, fine; narrow Draw a thin line between the columns Please slice the bread thin. 4 flimsy, weak, feeble, slight, unsubstantial, insubstantial, fragile, frail, poor, lame; unbelievable, unconvincing Harry gave some thin excuse for being late 5 airy, filmy, diaphanous, gossamer, sheer, light, delicate, chiffon, silky, silken, gauzy, translucent, see-through, transparent She had nothing but a thin negligee to protect her from the cold 6 watery, watered down, dilute(d), weak, unsatisfying My dinner, as usual, consisted of thin gruel and a dry crust 7 thin on the ground. rare, uncommon, scarce, few (and far between), unusual, hard to come by or find, scant, scanty Good managers are thin on the ground
v. 8 Often, thin down. draw out, attenuate, reduce, trim, cut down, prune; sharpen At one end, thin the dowel to a point 9 Often, thin down or out. dilute, water (down), decrease, reduce, diminish They always thin the wine with some water The crowd thinned out after a while.