Pith

17 clues
Gist
Crux
Core
Meat
Heart
Kernel
Marrow
Essence
Substance
Significance
Nitty-gritty
Central part
Quintessence
Inside stuff
Essential part
Crux of the matter
Heart of the matter
Similar answers:
1piece
Aaronbirth
Aaronburrconspiracy
Aattheopera
Aattheraces
Abandonedshipit
Abandonshippie
Abath
Abathingbeauty
Abdominalthrust
Abenchinthepark
Abernathy
Abguthrie
Abidebytherules
Abideceptivepitch
Abidingfaith
Abirdinthehand
Abirdinthesand
Abitontheside
Abookofthebible