Definition of feel one's age in US English:

feel one's age

phrase

  • Become aware that one is growing older and less energetic.

    • ‘He misses her terribly, and for the first time, he is truly feeling his age.’
    • ‘He doesn't feel his age, 61, and loves performing and meeting the fans that still flock to these performances.’
    • ‘I most certainly do not feel my age but we are made to feel that we are well and truly past it.’