sex gland vs orchis

sex gland and orchis both are nouns.

Word	Noun	Adjective	Verb	Adverb
sex gland	Yes	No	No	No
orchis	Yes	No	No	No

As nouns, orchis is a hyponym of sex gland; that is, orchis is a word with a more specific, narrower meaning than sex gland:

sex gland: a gland in which gametes (sex cells) are produced
orchis: one of the two male reproductive glands that produce spermatozoa and secrete androgens

Other hyponyms of sex gland include ovary, ovotestis, ball, ballock, bollock, egg, nut, testicle, testis.

sex gland (noun)	orchis (noun)
a gland in which gametes (sex cells) are produced	one of the two male reproductive glands that produce spermatozoa and secrete androgens
	any of various deciduous terrestrial orchids having fleshy tubers and flowers in erect terminal racemes