IPA: /ˌsɛmiˈæn.ju.əl/
KK: /sɛmiˈænjuəl/
Happening two times in a year, or every six months.
The company holds a semiannual meeting to discuss its progress.
Semiannual → It is formed from "semi-" (meaning half) and "annual" (from Latin "annus", meaning year). The word "semiannual" means occurring twice a year, or half-yearly.
Think of 'semi-' meaning half and 'annual' relating to a year — so semiannual refers to something that happens half as often as a full year.