Back-formations come in several flavors. Recently I’ve been posting on two-part back-formed (2-p b-f) verbs; a list of these postings is given below, for your reference. But there are also:
simple back-formed verbs (like incent);
nouns back-formed from nouns in -s, with the -s interpreted, ahistorically, as the mark of the plural (kudo);
other back-formed nouns (taxon, from taxonomy);
adjectives back-formed from negative adjectives by eliminating a negative prefix (couth);
other back-formed adjectives (gullible).
Back-formed verbs are hugely more numerous than the other types.
AZ, 8/22/08: To gay marry:
AZ, 11/2/08: Early/absentee vote (the verbs):
AZ, 4/5/09: scuba dove?: