Call for new fab dresses, showing how one may look (7)
I believe the answer is:
askance
'call for new fab dresses showing how one may look' is the definition.
I can't tell whether this defines the answer.
'call for new fab dresses' is the wordplay.
'call for' becomes 'ask' (synonyms).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'fab' becomes 'ace' (both can mean excellent).
'dresses' indicates putting letters inside (some letters are contained by or dressed in others).
'n' going into 'ace' is 'ance'.
'ask'+'ance'='ASKANCE'
Can you help me to learn more?
(Other definitions for askance that I've seen before include "Look this way in doubt or suspicion" , "(Look) disapprovingly" , "Indirectly" , "A look like this is sidelong or suspicious" , "In suspicious manner" .)