Kirk thought for a moment, trying to think how he might explain it, and there wasn't any paper around for him to draw it. So, considering that they were somewhat private and he was not overly shy, he turned his side towards Anders and hiked up his shirt to show the tattoo running down his rib cage.

"The symbol in the middle," he said, dropping his shirt when he was sure Anders had gotten a good look. "It's the symbol of the organization I work for - Star Fleet."