Cutting implement appears thinner, and neater (7)
I believe the answer is:
trimmer
'neater' is the definition.
('trim' can be a synonym of 'neat')
'cutting implement appears thinner' is the wordplay.
I cannot quite see how this works, but
'cutting' could be 'trim' (trim is a kind of cutting) and 'trim' is located in the answer.
The remaining letters 'mer' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'and' is the link.
Can you help me to learn more?
(Other definitions for trimmer that I've seen before include "Comparatively slender" , "in better order for > vicar of Bray?" , "Garden tool" , "Cutter; neater" , "Cutter for making things neat" .)