Synonyms of deficient in English:

deficient


See definition of deficient

adjective

1‘his diet is deficient in vitamin A’

SYNONYMS
lacking, wanting, defective, inadequate, insufficient, limited, poor, scant
short of, short on, low on, with an insufficiency of, with too few …, with too little …
informal strapped for, pushed for
ANTONYMS

excessive

2‘on all levels, this is deficient leadership’

SYNONYMS
defective, faulty, flawed, inadequate, imperfect, impaired, shoddy, scrappy, sketchy, weak, inferior, unsound, substandard, second-rate, poor, shabby, incomplete, leaving much to be desired
informal duff
ANTONYMS

perfect