Suitable travel make-up (4)
I believe the answer is:
good
'suitable' is the definition.
(similar in meaning)
'travel make-up' is the wordplay.
'travel' becomes 'go' (synonyms).
'make' becomes 'do' (synonyms).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'do' reversed gives 'od'.
'go'+'od'='GOOD'
(Other definitions for good that I've seen before include "Beneficial" , "Carol character from 1 as of old" , "To be desired; pleasing" , "Admirable" , "and 22 Down and 14 Across: Christmas carol" .)