opsimathy (n.)

"education late in life," 1650s, from Greek opsimathia "late learning," from opse "late, after a long time" (related to opiso "backward," opisthen "behind," from opi, a variant of epi "on it, at it;" see epi-) + manthanein "to learn" (from PIE root *mendh- "to learn"). Related: Opsimath (n.).