Is a cloth cap any different when greenish blue? (4)
I believe the answer is:
cyan
'greenish blue?' is the definition.
(I've seen this before)
'is a cloth cap any different' is the wordplay.
'is a cloth cap' becomes 'c' (I can't explain this - if you can you should give a lot more credence to this answer).
'different' is an anagram indicator (letters placed in a different order).
'any' is an anagram of 'yan'.
'c'+'yan'='CYAN'
'when' is the link.
Can you help me to learn more?
(Other definitions for cyan that I've seen before include "Blue printing ink" , "shade of blue" , "Printer's blue" , "Bluish green" , "Blue-green colour" .)