palindrome (n.)

"a word or line that reads the same backward and forward," 1620s, from Greek palindromos "a recurrence," literally "a running back." Second element is dromos "a running" (see dromedary); first is palin "again, back," from PIE *kwle-i-, suffixed form of root *kwel- (1) "revolve, move round." PIE *kw- becomes Greek p- before some vowels. Related: Palindromic; palindromist.