travail vs labor

travail and labor both are nouns.

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

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

Other hypernyms of travail include labour, toil.

As nouns, travail and labor are synonyms defined as:

travail and labor: concluding state of pregnancy; from the onset of contractions to the birth of a child

Other synonyms of travail include childbed, confinement, labour, lying-in, parturiency.

As verbs, travail and labor are synonyms defined as:

Other synonyms of travail include dig, drudge, fag, grind, labour, moil, toil.

travail (noun)	labor (noun)
use of physical or mental energy; hard work	productive work (especially physical work done for wages)
concluding state of pregnancy; from the onset of contractions to the birth of a child	any piece of work that is undertaken or attempted
	a social class comprising those who do manual labor or work for wages
	an organized attempt by workers to improve their status by united action (particularly via labor unions) or the leaders of this movement
	concluding state of pregnancy; from the onset of contractions to the birth of a child

travail (verb)	labor (verb)
work hard	undergo the efforts of childbirth
	work hard
	strive and make an effort to reach a goal