IPA: /ˌhɛmɪˈsfɪrɪkəl/
KK: /hɛmɪˈsfɪrɪkəl/
Having the shape of half a sphere.
The dome of the building is hemispherical, giving it a unique appearance.
Hemispherical → It is formed from "hemi-" (from Greek "hēmi-", meaning half) and "sphaira" (meaning sphere). The word describes something that is shaped like half of a sphere.
Think of 'half' ('hemi-') of a 'sphere' ('sphaira') — that's why hemispherical means shaped like half a sphere.