Source : Webster's Revised Unabridged Dictionary (1913)

Measurable \Meas"ur*a*ble\, a. [F. mesurable, L. mensurabilis.
   See {Measure}, and cf. {Mensurable}.]
   1. Capable of being measured; susceptible of mensuration or
      computation.

   2. Moderate; temperate; not excessive.

            Of his diet measurable was he.        --Chaucer.
      -- {Meas"ur*a*ble*ness}, n. -- {Meas"ur*a*bly}, adv.

            Yet do it measurably, as it becometh Christians.
                                                  --Latimer.

Source : WordNet®

measurably
     adv : to a measurable degree; "the difference is measurably large"
           [ant: {immeasurably}]