The definition of blasphemous is something profane, irreverent or disrespectful towards God or religion.(adjective)
Taking the Lord's name in vain is an example of something that would be described as blasphemous.
See blasphemous in Webster's New World College Dictionary
Origin: ME blasfemous < LL(Ec) blasphemus < Gr blasphēmos
See blasphemous in American Heritage Dictionary 4
Origin: Middle English blasfemous
Origin: , from Late Latin blasphēmus
Origin: , from Greek blasphēmos
Origin: , from blasphēmein, to blaspheme; see blaspheme.
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