What part of speech is tootles?

Tootles can be categorized as a noun and a verb.

Parts of speech

1. tootles is a verb, present, 3rd person singular of tootle (infinitive).
2. tootles is a noun, plural of tootle.

Verb
tootle - play (a musical instrument) casually; "the saxophone player was tootling a sad melody"
Noun
tootle - the sound of casual playing on a musical instrument; "he enjoyed hearing the tootles of their horns as the musicians warmed up"