wreckage vs lagan

wreckage and lagan both are nouns.

Word	Noun	Adjective	Verb	Adverb
wreckage	Yes	No	No	No
lagan	Yes	No	No	No

As nouns, lagan is a hyponym of wreckage; that is, lagan is a word with a more specific, narrower meaning than wreckage:

wreckage: the remaining parts of something that has been wrecked
lagan: goods (or wreckage) on the sea bed that is attached to a buoy so that it can be recovered

Other hyponyms of wreckage include flotsam, jetsam, lagend, ligan.

wreckage (noun)	lagan (noun)
the remaining parts of something that has been wrecked	goods (or wreckage) on the sea bed that is attached to a buoy so that it can be recovered