Measurement encompassing daughter alongside (5)
I believe the answer is:
width
'measurement' is the definition.
(width is a kind of measurement)
'encompassing daughter alongside' is the wordplay.
'encompassing' is an insertion indicator.
'daughter' becomes 'd'.
'alongside' becomes 'with' (I've seen this before).
'd' placed inside 'with' is 'WIDTH'.
(Other definitions for width that I've seen before include "Diameter" , "strip of material" , "Breadth" , "Lateral measurement" , "Range" .)