1640s, "left, abandoned by the owner or guardian," from Latin derelictus "solitary, deserted," past participle of dereliquere "to abandon, forsake, desert," from de- "entirely" (see de-) + relinquere "leave behind, forsake, abandon, give up," from re- "back" (see re-) + linquere "to leave," from PIE root *leikw- "to leave."
Originally especially of vessels abandoned at sea or stranded on shore. Of persona, "unfaithful, neglectful of responsibility," by 1864. As a noun, "property which is abandoned," from 1660s. As "person abandoned or forsaken," 1728.
