What types of words are these: Madam, Civic, Eye, Level?

Common Wrong Answers
“Anagram”
Anagrams are words formed by rearranging the letters of another word, not words that read the same backward.
“Homophone”
Homophones are words that sound the same but have different meanings or spellings, which does not relate to the concept of reading the same backward.
“Synonym”
Synonyms are words that have similar meanings, which is unrelated to the characteristic of reading the same in both directions.
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