(sports, snowboarding, skiing) Clipping of 1800. (1800° spin)

Suitable only for adults; mature.

plural of 18

A big rig truck: a semi-trailer plus the truck or tractor pulling it.

(physics) A minor stable isotope of oxygen, ¹⁸₈O, having eight protons and ten neutrons; it amounts to about 0.2% of the element in nature

(physics) An artificial radioisotope of fluorine, ¹⁸₉F, having 9 protons and 9 neutrons, that is an important industrial source of positrons

plural of 18-wheeler

(sports, slang) A round of golf.

Alternative form of 14-18; World War I

World War I