A carpool that consists of only family members. Also: fam-pool. [Blend of family and carpool.]
Approximately 80 percent of all carpools are made up of family members — "fampools" — who would commute together regardless of HOV incentives, according to Alan Pisarski, author of "Commuting in America."
In other words, you pay for the Jones family's trip, but you don't get to use their lane....
There are ways to align consumer demand with transit costs that create supply, however, that Massachusetts hasn't tried. Express toll lanes make drivers who want less congestion to pay for it, thereby generating revenue for new capacity. HOTV lanes — high occupancy lanes limited to car and vanpools paid for by employers who want to get their employees to work on time — eliminate the "fampool" subsidy of HOV lanes.
—Cornelius Chapman, "HOV lanes drive us commuters crazy," The Boston Herald, January 23, 2008
Exclusive bus-only lanes, like the semi-exclusive HOV ("high-occupancy vehicle") lanes that are common in the United States, further lessen the inherent efficiency of cars. Mr. O'Toole calls HOV lanes "fampool lanes" — because family size alone typically determines the number of people in any particular car at any particular time.
—Neil Reynolds, "The answer to urban traffic congestion? Cars," The Globe and Mail, May 23, 2008
The term carpool (or its still common variant car-pool) seems like a relatively new addition to the language, but it's older than you might think. The Oxford English Dictionary offers up an earliest citation from the December, 1942 edition of Reader's Digest: "I don't believe I care for anything, thank you. I'm just in their car pool." If you're wondering about vanpool, that term dates to about 1973.