spear thrower vs throwing stick

spear thrower and throwing stick both are nouns.

Word	Noun	Adjective	Verb	Adverb
spear thrower	Yes	No	No	No
throwing stick	Yes	No	No	No

As nouns, spear thrower and throwing stick are synonyms defined as:

spear thrower and throwing stick: a device resembling a sling that is used in various primitive societies to propel a dart or spear

Other synonyms of spear thrower include dart thrower, throwing board.

spear thrower (noun)	throwing stick (noun)
a device resembling a sling that is used in various primitive societies to propel a dart or spear	a curved piece of wood; when properly thrown will return to thrower
	a device resembling a sling that is used in various primitive societies to propel a dart or spear