Pacifier (noun)

An object, typically a rubber or plastic nipple or teething ring, given to a baby or young child to suck on as a means of calming or soothing them.

Origin:

From pacify + -er.

Examples:

1. The pacifier soothed the crying baby.
2. The pacifier helped to calm the child during the flight.
3. It's recommended to stop using pacifier by age 2 to prevent dental problems.
4. The pacifier is also known as a dummy or a soother.
5. Some parents prefer using pacifiers as a sleep aid for their babies.