spile vs sheath pile

spile and sheath pile both are nouns.

Word	Noun	Adjective	Verb	Adverb
spile	Yes	No	No	No
sheath pile	Yes	No	No	No

As nouns, sheath pile is a hyponym of spile; that is, sheath pile is a word with a more specific, narrower meaning than spile:

spile: a column of wood or steel or concrete that is driven into the ground to provide support for a structure
sheath pile: a pile in a row of piles driven side by side to retain earth or prevent seepage

Other hyponyms of spile include sheet pile, sheet piling.

spile (noun)	sheath pile (noun)
a plug used to close a hole in a barrel or flask	a pile in a row of piles driven side by side to retain earth or prevent seepage
a column of wood or steel or concrete that is driven into the ground to provide support for a structure