Synonyms and related words :
arid, awkward, barren, blah, blank, bloodless, blunt, blunt-witted, buckram, bumbling, cardboard, characterless, clumsy, cold, colorless, dead, deadpan, dim, dim-witted, dismal, dopey, draggy, drearisome, dreary, dry, dryasdust, dull, dull of mind, dull-headed, dull-pated, dull-witted, dusty, effete, elephantine, empty, etiolated, expressionless, fade, fat-witted, fishy, flat, gauche, glassy, gross-headed, halting, ham-handed, heavy, heavy-handed, hebetudinous, ho-hum, hollow, impassive, inane, inept, inexcitable, inexpressive, insipid, jejune, leaden, lifeless, low-spirited, maladroit, muscle-bound, obtuse, pale, pallid, pedestrian, plodding, pointless, poker-faced, poky, ponderous, slow, slow-witted, sluggish, solemn, spiritless, sterile, stiff, stilted, stodgy, stuffy, superficial, tasteless, tedious, thick-brained, thick-headed, thick-pated, thick-witted, thickskulled, unexpressive, unhandy, unhappy, unlively, vacant, vapid, weighty