flog vs lather

flog is not a noun while lather is a noun.

Word	Noun	Adjective	Verb	Adverb
flog	No	No	Yes	No
lather	Yes	No	Yes	No

As verbs, flog and lather are synonyms defined as:

Other synonyms of flog include lash, slash, strap, trounce, welt, whip.

flog (noun)	lather (noun)
	the froth produced by soaps or detergents
	the foam resulting from excessive sweating (as on a horse)
	a workman who puts up laths
	agitation resulting from active worry

flog (verb)	lather (verb)
beat severely with a whip or rod	rub soap all over, usually with the purpose of cleaning
beat with a cane	exude sweat or lather
	form a lather
	beat severely with a whip or rod