cackle vs blether

cackle and blether both are nouns.

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

As nouns, blether is a hyponym of cackle; that is, blether is a word with a more specific, narrower meaning than cackle:

Other hyponyms of cackle include chin music, idle talk, prate, prattle.

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

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