wick; marrow; core; heart; pistil (of a flower); stamen
center of a flower (centre); pistils and stamens
mentally strong; strong-willed
apple core; core of an apple
pencil lead case (for a mechanical pencil)
Chinese water spinach (Ipomoea aquatica); ong choy; kang kong; water morning glory; water convolvulus; swamp cabbage
thick obi sash; sash padding
padding; lining; foundation
thinning (buds and branches)
eccentricity (in mechanics, electronics, etc.)
pencil lead case (for mechanical pencil)
collar core (stiff fabric, etc. inside a collar)