What is the meaning of Nipple?

The projection of a mammary gland from which, on female therian mammals, milk is secreted.

The nipple (definition 1) and the areola together.

A mechanical device through which liquids or gases can be passed in a regulated manner.

An artificial nipple (definition 1) used for bottle-feeding infants.

Any small physical protrusion, such as the lumps on the F and J keys on computer keyboards.

Any small physical protrusion on an automotive, a machine part or any other part that fits into a groove on another part.

A perforated segment that fits into part of the breech of a muzzle-loading gun, on which the percussion cap is fixed.

A short tube threaded at both ends, used as a connector.

An internally threaded piece which holds a bicycle spoke in place on the rim.

A pointing stick.

To fit (a baby's bottle, etc.) with a nipple.

To give one's nipple to (a baby) to allow breastfeeding.

diminutive of neape

Source: wiktionary.org