IPA: /ˌsɛmɪˈsɜːrkjʊlər/
KK: /sɛmɪˈsɜrkjələr/
Having the shape of half a circle.
The garden was designed with a semicircular pathway that added elegance to the landscape.
Semicircular → It is formed from "semi-" (meaning half) and "circular" (from Latin "circularis", meaning circular or round). The word "semicircular" describes a shape that is half of a circle.
Think of 'half' ('semi-') of a 'circle' ('circular') — that's why semicircular refers to a shape that is half of a circle.