A slang term, rarely used nowadays, for a home run in baseball. Interchangeable with dinger, bomb, and homer, although "homer" is easily the most common term from baseball announcers and fans alike.
According to Merriam-Webster on-line, the term "tater" may have originated in the Negro Leagues of Professional Baseball early in the 20th century, where a home run was called a potato or long potato.
Example usage:
"How'd Clemente do today?"
"Coupla taters, four ribbies."
Sources: http://www.m-w.com/wftw/02may/050602.htm