slash vs thrash about

slash is a noun but thrash about is not a noun.

Word	Noun	Adjective	Verb	Adverb
slash	Yes	No	Yes	No
thrash about	No	No	Yes	No

As verbs, slash and thrash about are synonyms defined as:

Other synonyms of slash include convulse, jactitate, thrash, thresh, thresh about, toss.

slash (noun)	thrash about (noun)
a strong sweeping cut made with a sharp instrument
a punctuation mark (/) used to separate related items of information
an open tract of land in a forest that is strewn with debris from logging (or fire or wind)
a wound made by cutting

slash (verb)	thrash about (verb)
cut drastically	move or stir about violently
cut open
cut with sweeping strokes; as with an ax or machete
beat severely with a whip or rod
move or stir about violently