re #5

there's not THE "ow" sound.

Eben... Siehe "cow" (Substantiv) versus "low" (Adjektiv). Als nur ein Beispiel. Ist im Englischen ja mit vielen Buchstabenfolgen so! (ea ...)

On the topic of regional differences in the meaning of "frown":

As per Merriam Webster (online):

frown

\ ˈfrau̇n \

frowned; frowning; frowns

Definition of frown

 (Entry 1 of 2)

intransitive verb

1 : to contract the brow in displeasure or concentration frowned in anger

2 : to give evidence of displeasure or disapproval by or as if by facial expression critics frown on the idea

transitive verb

 : to show displeasure with or disapproval of especially by facial expression

I will be neither frowned nor ridiculed into error— Noah Webster

https://www.merriam-webster.com/dictionary/frown

As per Lexico (online):

frown

Pronunciation /fraʊn/

verb

[no object]

• 1Furrow one's brows in an expression indicating disapproval, displeasure, or concentration.
• ‘he frowned as he reread the letter’

1.1frown on/upon

Disapprove of.

‘promiscuity was frowned upon’

https://www.lexico.com/definition/frown

Based on the above, I don't see a difference between AE and BE.

Mein Eindruck entstand hier:

related discussion: His mouth dropped into a frown. - #13

I would say 'frown' refers to the corners of the mouth turning down, more than to anything with the eyebrows. (#4)

I disagree. I'd think of the eyebrows first, and only then perhaps the mouth.

Quote from a US novel (Passing, by Nella Larsen):

Her brows came together in a tiny frown. The frown, however, was more from perplexity than from annoyance; though there was in her thoughts an element of both.