the main points

meaning, essence

the softer, inner part (of a hut or fruit-stone); an inside part of a seed, e.g. a grain of wheat

seed, essence

an order, law or custom which guides or controls behaviour or action; a habit; authority; to govern (people, a country etc)

standard, principle of behavior

a subject of a talk or a piece of writing; a short tune used in a piece of music

idea, subject matter