Source : Webster's Revised Unabridged Dictionary (1913)

Alfresco \Al*fres"co\, adv. & a. [It. al fresco in or on the
   fresh.]
   In the open-air. --Smollett.

Source : WordNet®

alfresco
     adj : in the open air; "an alfresco lunch"; "an open-air theater"
           [syn: {open-air(a)}]
     adv : outside a building; "in summer we play outside" [syn: {outside},
            {outdoors}, {out of doors}] [ant: {inside}, {inside}]