Source : Webster's Revised Unabridged Dictionary (1913)

Howdy \How"dy\, n. [Scot., also houdy- wife. Of uncertain
   origin; cf. OSw. jordgumma; or perh. fr. E. how d'ye.]
   A midwife. [Prov. Eng.]

Source : WordNet®

howdy
     n : an expression of greeting; "every morning they exchanged
         polite hellos" [syn: {hello}, {hullo}, {hi}, {how-do-you-do}]