1. The wife of a count or earl.
  2. The title used by a female who holds an earldom in her own right.
    Elizabeth Millicent Leveson-Gower is 24th Countess of Sutherland; her son will be the 25th Earl.

The above text is a snippet from Wiktionary: countess
and as such is available under the Creative Commons Attribution/Share-Alike License.

Need help with a clue?
Try your search in the crossword dictionary!