Indeed, "bequest" is a noun. The dictionary usually indicates
such things, albeit as an abbreviation. "Bequested" would - did
it exist as a word, which apparently your dictionary does not
suggest - be as a _gerund_. Gerunds are nouns taking verb form.
Your dictionary will probably explain all this under the entry
"gerund," along with examples. Additionally, any standard
college freshman "rhetoric" should do so, at greater length.
(You may have to visit a used book store or rummage [woops!
that dates me too] garage sale to find one, as English is not
taught in schools any more.] Have you proof that there is a
recognized gerundive form of "bequest?"

Traditionally, nouns and verbs have been recognized as serving
different functions.

According to Arthur Harris:
>
> >Two observations: 1.) "The abbey was _bequeathed_, not
> >'bequested.'" Indeed, there is no such word. 2.) Whatever
> >happened to the principle of repatriation?
>
> My dictionary defines "bequest" as the act of bequeathing.
>