Source : Webster's Revised Unabridged Dictionary (1913)

Sociably \So"cia*bly\, adv.
   In a sociable manner.

Source : WordNet®

sociably
     adv 1: in a gregarious manner [syn: {gregariously}]
     2: in a sociable manner; "sociably, the new neighbors invited
        everyone on the block for coffee" [ant: {unsociably}]