absence vs deficiency

absence and deficiency both are nouns.

Word	Noun	Adjective	Verb	Adverb
absence	Yes	No	No	No
deficiency	Yes	No	No	No

As nouns, deficiency is a hypernym of absence; that is, deficiency is a word with a broader meaning than absence:

Other hypernyms of absence include lack, want.

absence (noun)	deficiency (noun)
failure to be present	lack of an adequate quantity or number
the state of being absent	the state of needing something that is absent or unavailable
the occurrence of an abrupt, transient loss or impairment of consciousness (which is not subsequently remembered), sometimes with light twitching, fluttering eyelids, etc.; common in petit mal epilepsy
the time interval during which something or somebody is away