Definition from Wiktionary, the free dictionary
longboard (plural longboards)
- (surfing) A large surfboard, around 9 or 10 feet long with a wide nose.
- In the past three weeks on Victoria's Surfcoast I've ridden my longboard probably 90% of the time as well. — Coastalwatch.com.au 
- A large skateboard, measuring about 90 to 150 centimeters.
- Alternative name of
- To travel by longboard.
spine board — see spine board