needfulformal
requisiteformal
SMART Vocabulary: related words and phrases
Essential or necessary
a man's gotta do what a man's gotta doidiom
baked in
basically
basis
be a question of doing somethingidiom
box ticking
elemental
gotta
hang
hang on/upon something
have occasion to do somethingidiom
if need beidiom
lifeline
meat and potatoesidiom
necessary
necessary evil
owe
symbiosis
symbiotic
symbiotically