spear vs javelin

spear and javelin both are nouns.

Word	Noun	Adjective	Verb	Adverb
spear	Yes	No	Yes	No
javelin	Yes	No	No	No

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

Other hyponyms of spear include assagai, assegai, pike, trident.

spear (noun)	javelin (noun)
a long pointed rod used as a tool or weapon	a spear thrown as a weapon or in competitive field events
an implement with a shaft and barbed point used for catching fish	an athletic competition in which a javelin is thrown as far as possible

spear (verb)	javelin (verb)
pierce with a spear
thrust up like a spear