The Collaborative International Dictionary of English v.0.48:

Fourscore \Four"score`\ (f[=o]r"sk[=o]r`), a. [Four + core, n.]
   Four times twenty; eighty.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Fourscore \Four"score`\, n.
   The product of four times twenty; eighty units or objects.
   [1913 Webster]

WordNet (r) 3.0 (2006):

fourscore
    adj 1: being ten more than seventy [syn: eighty, 80, lxxx,
           fourscore]
    n 1: the cardinal number that is the product of ten and eight
         [syn: eighty, 80, LXXX, fourscore]