son of Laius and Jocasta, the king and queen of Thebes, from Greek Oidipous, literally "swollen-foot," from oidan "to swell" (from PIE *oid-; see edema) + pous (genitive podos) "foot," from PIE root *ped- "foot." Shelley titled his play based on Sophocles' work "Swellfoot the Tyrant." Oedipus complex (1910) was coined by Freud. In Latin, figurative references to Oedipus generally referred to solving riddles. Oedipus effect (1957) is Karl Popper's term for "the self-fulfilling nature of prophecies or predictions."