sea-coast vs landfall

sea-coast and landfall both are nouns.

Word	Noun	Adjective	Verb	Adverb
sea-coast	Yes	No	No	No
landfall	Yes	No	No	No

As nouns, landfall is a hyponym of sea-coast; that is, landfall is a word with a more specific, narrower meaning than sea-coast:

Other hyponyms of sea-coast include litoral, littoral, littoral zone, sands, seaboard, seaside, tideland.

sea-coast (noun)	landfall (noun)
the shore of a sea or ocean	the first sighting of land from the sea after a voyage (or flight over water)
	the seacoast first sighted on a voyage (or flight over water)