scotoma

The story

1. Ancient Greek · derived fromσκότωμα
2. Late Latin · derived fromscotoma
3. English todayscotoma

From Late Latin scotoma, from Ancient Greek σκότωμα (skótōma), from σκότος (skótos, “darkness”). By surface analysis, scot- + -oma. The figurative sense is an extension from the literal sense, as if the mind, like an eye, cannot "see" certain things.