Pacifier: An artificial nipple, usually made of plastic, upon which an infant can suck to gain some solace and quiet down. A pacifier is called by other names in other countries including a "dummy" in the U.K.
Pacifiers have been claimed to cause early weaning. However, a study (JAMA, July 18, 2001) was done of women who were planned to breastfeed for at least 3 months. All of the women were told how to soothe a crying or fussy child, but one group of women was told to avoid giving their baby a pacifier. Advising women not to give their baby a pacifier had no effect. The rate of early weaning was the same in both groups. The use of a pacifier does not cause early weaning.