Sheesh.... It was because it was a 732 in today's world... Not that it was a 737.
noun (plural ironies)
the expression of one’s meaning by using language that normally signifies the opposite, typically for humorous or emphatic effect:
‘Don’t go overboard with the gratitude,’ he rejoined with heavy irony
a state of affairs or an event that seems deliberately contrary to what one expects and is often wryly amusing as a result:
the irony is that I thought he could help me
one of life’s little ironies
(also dramatic or tragic irony) a literary technique, originally used in Greek tragedy, by which the full significance of a character’s words or actions is clear to the audience or reader although unknown to the character.
early 16th century (also denoting Socratic irony): via Latin from Greek eirōneia 'simulated ignorance', from eirōn 'dissembler'(source: Oxford English dictionary)