Wordnet 3.0
ADVERB (1)
1. 
 in a quantitative manner; 
- Example: "this can be expressed quantitatively"
The Collaborative International Dictionary of English v.0.48:
Quantitative \Quan"ti*ta*tive\, a. [Cf. F. quantitatif.]
   Relating to quantity. -- Quan"ti*ta*tive*ly, adv.
   [1913 Webster]
   Quantitative analysis (Chem.), analysis which determines
      the amount or quantity of each ingredient of a substance,
      by weight or by volume; -- contrasted with qualitative
      analysis.
      [1913 Webster]
WordNet (r) 3.0 (2006):
quantitatively
    adv 1: in a quantitative manner; "this can be expressed
           quantitatively"