difficulty vs travail

difficulty and travail both are nouns.

Word	Noun	Adjective	Verb	Adverb
difficulty	Yes	No	No	No
travail	Yes	No	Yes	No

As nouns, travail is a hypernym of difficulty; that is, travail is a word with a broader meaning than difficulty:

Other hypernyms of difficulty include effort, elbow grease, exertion, sweat.

difficulty (noun)	travail (noun)
an effort that is inconvenient	use of physical or mental energy; hard work
the quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result	concluding state of pregnancy; from the onset of contractions to the birth of a child

difficulty (verb)	travail (verb)
	work hard