Social worker crosses very large slope (5)
I believe the answer is:
bevel
'slope' is the definition.
(thesaurus)
'social worker crosses very large' is the wordplay.
'social worker' becomes 'bee' (bees work socially).
'crosses' indicates putting letters inside.
'very' becomes 'v' (abbreviation).
'large' becomes 'L' (eg in clothes sizes).
'bee' enclosing 'v' is 'beve'.
'beve'+'l'='BEVEL'
(Other definitions for bevel that I've seen before include "Sloping join" , "Two flat surfaces meeting at other than a right angle" , "Cut at a slant" , "Slanting surface" , "Cant" .)