Merriam-Webster's Collegiate® Dictionary, 11th Edition
DIMENSION
I. noun see: measure
Date: 14th century
1. a. measure in one direction, one of a group of properties whose number is necessary and sufficient to determine uniquely each element of a system of usually mathematical entities (as an aggregate of points in real or abstract space) , the number of elements in a basis of a vector space, the quality of spatial extension ; magnitude , size , a lifelike or realistic quality, the range over which or the degree to which something extends ; scope , one of the elements or factors making up a complete personality or entity ; aspect , bodily form or proportions, any of the fundamental units (as of mass, length, or time) on which a derived unit is based, wood or stone cut to pieces of specified size, a level of existence or consciousness, dimensional adjective dimensionality noun dimensionally adverb dimensionless adjective
II. transitive verb (dimensioned; dimensioning)
Date: 1754
to form to the required dimensions, to indicate the dimensions of (as on a drawing)