Related Clues:

• Inside skin of, say, orange
• Central point or core of matter
• Gist, central idea
• The essential point of the matter
• Core of a bun
• The central point of anything
• The essential point of something
• White inner skin of an orange
• Essential idea
• Central point of issue
• General meaning or main point
• 'Gist, central idea (3)'
• Central meaning or theme
• Inner skin of citrus fruit
• Substance or general idea