Here's why:
* "Tosses" is the plural form of the verb "to toss." Verbs don't typically have adjective forms.
* To describe something related to tossing, you would use adjectives like:
* Tossable (able to be tossed)
* Tossed (having been tossed)
* Tossing (in the act of tossing)
For example, you could say "He made a tossed salad" or "The tossed ball landed in the net."