Crossword clue: a defect of vision consequent upon advancing age. it is due to rigidity of the crystalline lens, which producepresbytia.
1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).
Possible answers
a reduced ability to focus on near objects caused by loss of elasticity of the crystalline lens after age 45