Nuts and bolts - assonance.

So I was in a branch of a well-known chemist looking for something to give my hair a bit of life (see photo opposite - which, I must point out, is an AFTER shot).

Anyway.

Some sort of a mousse or gell-type thing, I thought. I mean, I don't want to look like an electrocuted poodle, I just need something to give my roots a bit of a lift.

Everything was quite expensive, though, and I couldn't find an own--brand.
So I looked around for someone to ask about a Boots Root-Boost Mousse...

...and decided to get the Phil Smith one, instead.

Assonance. I have always understood that assonance is when a vowel sound is repeated, as in cool moon, or past-master or I may reply to Hugh through you.
Everyone I have consulted seems to agree with me apart from the Collins dictionary, which includes mystery/mastery as an example of assonance.
I would have called this a half-rhyme, or slant-rhyme, or para-rhyme, myself.

I suspect I might even be right, too.

Assonance: from the Latin word assonāre which means, rather dully, to sound.

Hey, I bet you can't say Boots Root-Boost Mousse, either!