n.
Function: adjective
Date: 1557
1 : having four units or members
2 : being four times as great or as many
3 : marked by four beats per measure < quadruple meter>
– qua · dru · ply \ - ' drü-pl ē , - ' dr ə -, -dr ə - \ adverb
– qua · dru · plic · i · ty \ ˌ kwä-dru ̇ - ' pli-s ə -t ē \ noun