Divide in two (5)
'divide in two' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for halve that I've seen before include "Cut down substantially" , "Divide into two equal pieces" , "cut by fifty percent" , "Share equally" , "Reduce by 50%" .)
'divide in two' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for bisect that I've seen before include "Divide into two equal parts" , "cross" , "Cut twenty [IN TWO]" , "Cut or divide in two" , "Cut equally in two" .)