Stalk; staunch (4)
I believe the answer is:
stem
I believe this is a double definition.
'stalk' is the first definition.
(synonyms)
'staunch' is the second definition.
(synonyms)
(Other definitions for stem that I've seen before include "Main part of noun or verb" , "It supports a plant" , "root" , "supporter of flag, for example" , "Tube" .)