Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
astigmia is a noun meaning "(ophthalmology) impaired eyesight resulting usually from irregular conformation of the cornea; common in nearsighted people". It carries 2 recorded senses.
(ophthalmology) impaired eyesight resulting usually from irregular conformation of the cornea; common in nearsighted people
ophthalmology
(optics) defect in an optical system in which light rays from a single point fail to converge in a single focal point
optics
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for astigmia come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.