(1):

(n.) The navel.

(2):

(n.) The middle or body of a church, extending from the transepts to the principal entrances, or, if there are no transepts, from the choir to the principal entrance, but not including the aisles.

(3):

(n.) The block in the center of a wheel, from which the spokes radiate, and through which the axle passes; - called also hub or hob.