age•ing (BrE) (also aging NAmE, BrE) noun, adjectiveBrE /ˈeɪdʒɪŋ/NAmE /ˈeɪdʒɪŋ/noun [uncountable] the process of growing oldsigns of ageingskin care products which claim to halt the ageing process adjective [usually before noun] becoming older and usually less useful, safe, healthy, etcageing equipmentan ageing rock starHe takes care of his ageing mother.