SYNONYMS
apathetic, passive, unenthusiastic, lifeless, listless, lacking in vitality, weak, feeble, spineless, droopy, limp, languid, bloodless, insipid, characterless, submissive, meek, irresolute, indecisive
lacklustre, flat, colourless, passionless, uninspiring, uninspired, wooden, dry, desiccated, unimpassioned, anaemic, vapid, dull, boring
informal wishy-washy
British vulgar slang half-arsed
North American vulgar slang half-assed