Highest point almost for pulse (3)
I believe the answer is:
pea
'pulse' is the definition.
(thesaurus)
'highest point almost' is the wordplay.
'highest point' becomes 'peak' (I've seen this before).
'almost' means to remove the last letter (most of the word but not all of it).
'peak' with its last letter taken away is 'PEA'.
'for' acts as a link.
(Other definitions for pea that I've seen before include "It may climb frame" , "veg" , "Spherical vegetable" , "12 in a pod" , "Ape this plant awkwardly" .)