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(plural scotomata), 1540s, from Late Latin scotoma, from Greek skotoma "dizziness," from skotoun "to darken," from skotos "darkness" (see shade).
scotoma sco·to·ma (skə-tō'mə)n. pl. sco·to·mas or sco·to·ma·ta (-mə-tə)
An area of diminished vision within the visual field.
See blind spot.