Show of concern? Not to women on vacation (5)
I believe the answer is:
frown
'show of concern?' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'not to women on vacation' is the wordplay.
'not to' becomes 'fro' (I've seen this in another clue).
'on vacation' suggests removing the centre (after the inside letters have vacated the word).
'women' with its middle taken out is 'wn'.
'fro'+'wn'='FROWN'
Can you help me to learn more?
(Other definitions for frown that I've seen before include "Dirty look" , "Furrow one's brow" , "Facial expression of dislike or concentration" , "Sullen look" , "Wrinkling of forehead" .)