thirty Meaning, Definition & Usage

  1. noun the cardinal number that is the product of ten and three
    XXX; 30.
  2. adjective satellite being ten more than twenty
    xxx; 30.

WordNet

Thir"ty adjective
Etymology
OE. thritty, AS. Þritig, Þrittig; akin to D. dertig, G. dreissig, Icel. Þrjatiu, Þrjatigi, Þrir teger, Goth. Þreis tigjus, i.e., three tens. See Three, and Ten, and cf. Thirteen.
Definitions
  1. Being three times ten; consisting of one more than twenty-nine; twenty and ten; as, the month of June consists of thirty days.
Thir"ty noun
Wordforms
plural Thirties
Definitions
  1. The sum of three tens, or twenty and ten; thirty units or objects.
  2. A symbol expressing thirty, as 30, or XXX.

Webster 1913