irony -- Mom

i·ro·ny  (r-n, r-) n. pl. i·ro·nies 1. a. The use of words to express something different from and often opposite to their literal meaning. b. An expression or utterance marked by a deliberate contrast between apparent and intended meaning. c. A literary style employing such contrasts for humorous or rhetorical effect. See Synonyms at wit1. 2. a. Incongruity between what might be expected and what actually occurs: "Hyde noted the irony of Ireland's copying the nation she most hated" (Richard Kain). b. An occurrence, result, or circumstance notable for such incongruity. See Usage Note at ironic. 3. Dramatic irony. 4. Socratic irony. [French ironie, from Old French, from Latin rna, from Greek eirneia, feigned ignorance, from eirn,dissembler, probably from eirein, to say; see wer-5 in Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved

It is ironic that Mom's retired and she's working overtime.