field trip vs expedition

field trip and expedition both are nouns.

Word	Noun	Adjective	Verb	Adverb
field trip	Yes	No	No	No
expedition	Yes	No	No	No

As nouns, expedition is a hypernym of field trip; that is, expedition is a word with a broader meaning than field trip:

field trip: a group excursion (to a museum or the woods or some historic place) for firsthand examination
expedition: a journey taken for pleasure

Other hypernyms of field trip include excursion, jaunt, junket, outing, pleasure trip, sashay.

field trip (noun)	expedition (noun)
a group excursion (to a museum or the woods or some historic place) for firsthand examination	a journey organized for a particular purpose
	a military campaign designed to achieve a specific objective in a foreign country
	a journey taken for pleasure
	the property of being prompt and efficient
	an organized group of people undertaking a journey for a particular purpose