irony (n.)
c.1500, from Latin ironia, from Greek eironeia "dissimulation, assumed ignorance," from eiron "dissembler," perhaps related to eirein "to speak" (see verb). Used in Greek of affected ignorance, especially that of Socrates. For nuances of usage, see humor. Figurative use for "condition opposite to what might be expected; contradictory circumstances" is from 1640s.
irony (adj.)
"of or resembling iron," late 14c., from iron (n.) + -y (2).