Noticed far side of lawn is cut (4)
I believe the answer is:
sawn
'is cut' is the definition.
(cut with a saw)
'noticed far side of lawn' is the wordplay.
'noticed' becomes 'saw'.
'far side of' suggests the final letters.
The final letter of 'lawn' is 'n'.
'saw'+'n'='SAWN'
(Other definitions for sawn that I've seen before include "Severed" , "Cut with serrated blade" , "(Of wood) cut" , "timber must be" , "went up and down?" .)