about the phrase "beastly red hair"

[Klpno]

Hello everyone
I'd like to ask about the phrase "beastly red hair".

The author describes an appereance:

...her head topped with beastly red hair...

I looked up "beastly" in several dictionaries but still cannnot figure out the meaning in the phrase and I'm not even sure if this word is an adjective, or adverb in this case.

beast·ly /ˈbistli/ Pronunciation Key - Show Spelled Pronunciation[beest-lee] Pronunciation Key - Show IPA Pronunciation adjective, -li·er, -li·est, adverb
–adjective
1. of or like a beast; bestial.
2. Informal. nasty; unpleasant; disagreeable.
–adverb
3. Chiefly British Informal. very; exceedingly: It's beastly cold out.
4. British Informal. disagreeably; outrageously: beastly rude.

It seems to me that in "with beastly red hair" the intended meaning is "extremely" but I'm not sure.

[Yankee]

Hi KLPNO

I'd say the author was categorizing her hair negatively, so it might be better to interpret 'beastly red hair' as 'red hair that was disagreeable and outrageous'.
.

[Klpno]

Hi Amy

Thank you very much.