'Threshold' in the Bible

In those days Mordecai [was] sitting at the gate of the king. Bigthana and Teresh, two of the king's eunuchs from the keepers of the threshold, became angry and they conspired {to assassinate} King Ahasuerus.

And it was found written how Mordecai had reported concerning Bigthana and Teresh, two of the king's eunuchs from the keepers of the threshold who had conspired {to assassinate} King Ahasuerus.