Pun

In The Importance of Being Earnest, the pun, to be the lowest form of verbal wit. The pun in the title is a case in point. The earnest/Ernest joke strikes at the very heart of Victorian notions of respectability and duty. Gwendolen wants to marry a man called Ernest, and she doesn't care whether the man actually possesses the qualities that comprise earnestness. She is, after all, quick to forgive Jack's deception. In embodying a man who is initially neither “earnest” nor “Ernest,” and who, through forces beyond his control, subsequently becomes both “earnest” and “Ernest,” Jack is a walking, breathing paradox and a complex symbol of Victorian hypocrisy.

Bunbury (is a person who Algernon made up)- Osacar Wilde using it as a homosexual pun.