chigger vs flea

chigger and flea both are nouns.

Word	Noun	Adjective	Verb	Adverb
chigger	Yes	No	No	No
flea	Yes	No	No	No

As nouns, flea is a hypernym of chigger; that is, flea is a word with a broader meaning than chigger:

chigger: small tropical flea; the fertile female burrows under the skin of the host including humans
flea: any wingless bloodsucking parasitic insect noted for ability to leap

chigger (noun)	flea (noun)
larval mite that sucks the blood of vertebrates including human beings causing intense irritation	any wingless bloodsucking parasitic insect noted for ability to leap
small tropical flea; the fertile female burrows under the skin of the host including humans