Most tidy (8)
'most tidy' is the definition.
('neat' can be similar in meaning to 'tidy')
This is all the clue.
(Other definitions for neatest that I've seen before include "Seat ten (anag)" , "Most orderly" , "Most tidy" , "Most smart" , "best-looking desk, say?" .)
'most tidy' is the definition.
('clean' is associated in meaning with 'tidy')
This is the entire clue.
(Other definitions for cleanest that I've seen before include "Most hygienic" , "Most dirt-free" .)