bigamy vs wedlock

bigamy and wedlock both are nouns.

Word	Noun	Adjective	Verb	Adverb
bigamy	Yes	No	No	No
wedlock	Yes	No	No	No

As nouns, wedlock is a hypernym of bigamy; that is, wedlock is a word with a broader meaning than bigamy:

bigamy: the state of having two spouses at the same time
wedlock: the state of being a married couple voluntarily joined for life (or until divorce)

Other hypernyms of bigamy include marriage, matrimony, spousal relationship, union.

bigamy (noun)	wedlock (noun)
the offense of marrying someone while you have a living spouse from whom no valid divorce has occurred	the state of being a married couple voluntarily joined for life (or until divorce)
the state of having two spouses at the same time