Rodney William Whitaker (Granville, NY, USA, June 12, 1931 – West Country, England, December 14, 2005) was an American film scholar and writer who wrote several successful novels under the pen name Trevanian.

Between 1972 and 1983, five of his novels sold more than a million copies each. His first novel, published at the age of forty when he was teaching at the University of Texas, was The Eiger Sanction, an intelligent, gritty and thrilling spy spoof. It became a worldwide best seller. In 1975 it was adapted as a movie directed by and starring Clint Eastwood. – Saddened that some critics did not "get" the spoof contained in The Eiger Sanction, Trevanian followed it with an even more intense spoof, The Loo Sanction (1973), which depicted an ingenious art theft. Then came The Main (1976), a roman policier set in a poor neighborhood of Montreal, featuring widowed fiftyish police lieutenant Claude LaPointe. Next came Shibumi in 1979, Trevanian's meta-spy novel, which received the most critical acclaim. In 1983 he published The Summer of Katya, a psychological horror novel. In 1998 Trevanian reappeared as the author of a Western novel called Incident at Twenty-Mile, and a collection of short stories, Hot Night in the City (2000).

Under the name Nicolas Seare, Trevanian also published 1339 or So: Being an Apology for a Pedlar (1975), a witty medieval tale of love and courage; and Rude Tales and Glorious (1983), a bawdy re-telling of Arthurian tales. In his obituary in the New York Times, Whitaker was described as the only writer of airport paperbacks to be compared to Zola, Ian Fleming, Poe and Chaucer.