Common way for Americans writing about colour? (3-1)
I believe the answer is:
non-u
'common' is the definition.
(as in U and non-U speech)
'way for americans writing about colour?' is the wordplay.
I cannot really understand how this works, but
'way' could be 'n' (Compass direction - North) and 'n' is present in the answer.
'about' could be 'on' (as in a book 'on' a certain topic) and 'on' is located in the answer.
A single letter 'u' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
(Other definitions for non-u that I've seen before include "Not socially acceptable" , "Socially naff" , "Lower class" , "Not characteristic of the upper classes" , "Not socially refined" .)