1. (noun) the choicest or most essential or most vital part of some idea or experience

• center
• centre
• core
• essence
• gist
• heart
• inwardness
• kernel
• marrow
• meat
• nitty-gritty
• nub
• pith
• substance
• sum

2. (adverb) with complete faith

• body and soul

1. (noun) the choicest or most essential or most vital part of some idea or experience

• bare bones
• haecceity
• quiddity
• hypostasis
• quintessence
• stuff

1. (noun) the choicest or most essential or most vital part of some idea or experience

• cognitive content
• content
• mental object

1. (noun) the choicest or most essential or most vital part of some idea or experience

• all important
• all-important
• crucial
• essential
• of the essence
• cardinal
• central
• fundamental
• key
• primal
• meaty
• substantive
• pithy
• sententious
• summate