Synonyms of inefficient in English:

inefficient


See US English definition of inefficient

See UK English definition of inefficient

See Spanish definition of ineficiente

adjective

1‘my boss thinks I'm inefficient’

SYNONYMS
ineffective, ineffectual, inefficacious, incompetent, inept, incapable, unfit, unsuitable, unskilled, unskilful, inexpert, amateurish
disorganized, badly organized, unprepared, undisciplined, negligent, lax, slipshod, sloppy, slack, remiss, careless
informal lousy, useless
British vulgar slang couldn't organize a piss-up in a brewery
ANTONYMS

efficient

2‘a series of elaborate and inefficient processes’

SYNONYMS
uneconomical, wasteful, purposeless, unproductive, time-wasting, slow, slow-moving, awkward, unwieldy, cumbersome, badly arranged, deficient, disorganized, unsystematic
ANTONYMS

efficient