Manjar (man' jah) n. The jar, cup or bowl full of coins that is located somewhere in every man's bedroom.
Mansoon (man' soon) n. The sharp intake of breath when a young woman passes a group of business guys, and they all suck in their stomachs.
Mapparition (map a' ri shun) n. The spooky run of green lights you get whenever you desperately need to stop the car and consult the map.
Mashticate (mash' ti kayt) v. To use mashed potato as a means of capturing and consuming any peas left on your plate.
Mateneering (mayt' en ear ing) n. The competition between two men to climb to the top of anything.
Mergeician (merj' i shun) n. The rare person who stops and lets you into a stream of traffic, making a space suddenly appear out of nowhere.
Source: Richard Glovers list of words that should exist - but don't