10 letters · 17 points in Scrabble
noun a board with wheels that is ridden in a standing or crouching position and propelled by foot
verb ride on a flat board with rollers attached to the bottom
originFrom skate + board. The foot-treadable skateboard sense (noun sense 1) came first (mid-20th century). The vehicle chassis sense (noun sense 2) was named for its resemblance thereto (late 20th or early 21st century).
Etymology from Wiktionary, CC BY-SA 3.0