1. (n.) A mark or depression in the middle of the abdomen; the umbilicus; the bellybutton\.

2. (n.) The central part or point of anything; the middle.

3. (n.) An eye on the under side of a carronade for securing it to a carriage.

axis center center of action center of gravity centroid centrum core dead center epicenter heart hub kernel marrow medulla metacenter middle nave nub nucleus omphalos pith pivot storm center umbilicus