thrower vs tosser

thrower and tosser both are nouns.

Word	Noun	Adjective	Verb	Adverb
thrower	Yes	No	No	No
tosser	Yes	No	No	No

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

thrower: someone who projects something (especially by a rapid motion of the arm)
tosser: someone who throws lightly (as with the palm upward)

Other hyponyms of thrower include pelter, hurler, pitcher, twirler, slinger.

thrower (noun)	tosser (noun)
someone who projects something (especially by a rapid motion of the arm)	someone who throws lightly (as with the palm upward)
a craftsman who shapes pottery on a potter's wheel and bakes them in a kiln	terms of abuse for a masturbator
a person who twists silk or rayon filaments into a thread or yarn