The term 'not giving up' can be summarized by two crossword solutions: PERSISTENT (10 letters) and intherepitching (15 letters). PERSISTENT means continuing to do something despite difficulty or delay in achieving success. Intherepitching is a combination of the words 'in the re-pitching' which implies that one is not giving up and is instead trying again. Both terms suggest that someone is determined to keep going despite any obstacles they may face.