Entry 3 senses · 2 variants Webster, 1913 Sixty /sĭksʹtē/ · Six·ty · IPA /ˈsɪksti/ a. n. 01 a. Six times ten; fifty-nine and one more; threescore. 1. Six times ten; fifty-nine and one more; threescore. 02 n. The sum of six times ten; sixty units or objects. pl. Sixties 1. The sum of six times ten; sixty units or objects. 2. A symbol representing sixty units, as 60, lx., or LX.