'Irresponsibly' definitions:

Definition of 'irresponsibly'

From: WordNet
adverb
In an irresponsible manner; "he acted irresponsibly" [ant: responsibly]

Definition of 'Irresponsibly'

From: GCIDE
  • Irresponsibly \Ir`re*spon"si*bly\, adv.
  • 1. So as not to be responsible. [1913 Webster]
  • 2. In an irresponsible[2] manner; without due care or diligence. [PJC]