n. An activist who promotes breast-feeding over the use of infant formula.
During the 1990s, Sears established himself as the most visible breast-feeding spokesman in the United States. … So loyal fans and followers of Sears were shocked to find that his site featured prominent banner ads promoting infant formula. … AskDrSears.com, which debuted in November, represents Sears' bid to expand his media presence to the Internet. The site has become the target of an angry letter-writing campaign by pro-breast-feeding parents, medical professionals and 'lactivists' all over the world.
Become a Lactivist!: The Very Best Resources for Learning More About Breastfeeding Advocacy
This word is a satisfying blend of the prefix lacto-, "milk" and activist. A synonym (seen almost exclusively on the Web) is nipple Nazi. Many thanks to subscriber Clint Stevens for letting me know about this term.