palindrome

UK: /ˈpælɪnˌdrəʊm/ US: /ˈpælɪnˌdroʊm/ ,(pal′in drōm′)

WordReference Random House Learner's Dictionary of American English © 2025

pal•in•drome /ˈpælɪnˌdroʊm/   n. [countable]

1. a word, line, verse, number, etc., reading the same backward and forward, as
   Madam, I'm Adam.

See -drom-.

WordReference Random House Unabridged Dictionary of American English © 2025

pal•in•drome  (pal′in drōm′), n. 

1. a word, line, verse, number, sentence, etc., reading the same backward as forward, as Madam, I'm Adam or Poor Dan is in a droop.
2. Biochemistry, Genetics a region of DNA in which the sequence of nucleotides is identical with an inverted sequence in the complementary strand:
   GAATTC is a palindrome of CTTAAG.

• Greek palíndromos recurring, equivalent. to pálin again, back + -dromos running (see -drome)
• 1620–30;

pa•lin•dro•mist  (pə lin′drō mist), n.  pal•in•drom•ic  (pal′in drom′ik, -drō′mik), pal′in•drom′i•cal, adj.  pal′in•drom′i•cal•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

palindrome / ˈpælɪnˌdrəʊm/ noun

1. a word or phrase the letters of which, when taken in reverse order, give the same word or phrase, such as able was I ere I saw Elba

Etymology: 17th Century: from Greek palindromos running back again, from palin again + -drome

palindromic / ˌpælɪnˈdrɒmɪk/, palindromical / ˌpælɪnˈdrɒmɪkəl/ adjective