Is "handphone" idiomatic?

Question

My native language is Malay and I use the word "handphone" the whole time. Even when speaking in Malay, the Malay equivalent "telefon bimbit" sounds stiff.

This word is found in Lexico and marked South East Asian:

Handphone
South East Asian
A mobile phone

As far as I know, BrE and AmE speakers use "mobile phone" and "cell phone", respectively. So I'd like to know what native speakers feel about this word "handphone".

Here's an example from Lexico:

The idea is to prove to the big boys that it can be done, and that consumers can live with a handphone and mobile Internet.

Here are a few questions I'd like to ask:

1. Is this idiomatic to BrE and AmE speakers?
2. Can I use it in my thesis or term paper?
3. Is it best avoided?

Answer 1

1. In AmE, this is not idiomatic. It made me think of a cell phone operated by crank or something ;)
   I'm not as familiar with BrE, but I imagine it is also not idiomatic in BrE either. We can take a look at Ngram for clues: (handphone: eng_gb_2019),(cell phone: eng_gb_2019),(mobile phone: eng_gb_2019).

Just out of curiosity, I took a look at AmE books: (handphone: eng_us_2019),(cell phone: eng_us_2019),(mobile phone: eng_us_2019)

So in either case, handphone is hardly used.

2. and 3. Just keep your audience in mind. If you know your audience uses handphone and they're comfortable with that, then use that. If it's an international audience, use cell phone or mobile phone Either one will be understood.