Puzzle on 1/25/03

A palindrome is a word, phrase, or sentence that reads the same backwards or forwards.
For example, the word DAD is a palindrome.
The phrase A SANTA AT NASA is a palindrome.

This week, I will give you clues about a particular palindrome.
Your task is to discover the palindrome from my clues.

I am thinking of a one word palindrome.

The word means
something that runs on a track

What is the word?

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