Etymology: Middle English thikke, from Old English thicce; akin to Old High German dicki thick, Old Irish tiug
Date: before 12th century
1 a: having or being of relatively great depth or extent from one surface to its opposite <a thick plank>b: heavily built :thickset 2 a: close-packed with units or individuals <the air was thick with snow>b: occurring in large numbers :numerousc: viscous in consistency <thick syrup>d:sultry, stuffye: marked by haze, fog, or mist <thick weather>f: impenetrable to the eye :profound<thick darkness>g: extremely intense <thick silence> 3: measuring in thickness <12 inches thick> 4 a: imperfectly articulated :indistinct<thick speech>b: plainly apparent :decided<a thick French accent>c: producing inarticulate speech <a thick tongue> 5:obtuse, stupid<too thick to understand> 6: associated on close terms :intimate<was quite thick with his pastor> 7: exceeding bounds of propriety or fitness :excessive<called it a bit thick to be fired without warning>