blether vs cackle

blether and cackle both are nouns.

Word	Noun	Adjective	Verb	Adverb
blether	Yes	No	Yes	No
cackle	Yes	No	Yes	No

As nouns, cackle is a hypernym of blether; that is, cackle is a word with a broader meaning than blether:

Other hypernyms of blether include chatter, yack, yak, yakety-yak.

blether (noun)	cackle (noun)
idle or foolish and irrelevant talk	a loud laugh suggestive of a hen's cackle
	noisy talk
	the sound made by a hen after laying an egg

blether (verb)	cackle (verb)
to talk foolishly	emit a loud, unpleasant kind of laughing
	squawk shrilly and loudly, characteristic of hens
	talk or utter in a cackling manner
	make a noise characteristic of a goose