As nouns the difference between bastid and baetid
is that bastid is eye dialect of bastard, someone with illegitimate parentage while baetid is any member of the Baetidae.
bastid
English
Noun
(
en noun)
(slang, vulgar) , someone with illegitimate parentage. baetid
English
Noun
(
en noun)
(zoology) Any member of the Baetidae.