From Longman Dictionary of Contemporary Englishsemisem‧i /ˈsemi/ noun (plural semis) [countable] 1 British English informalDHH a semi-detached house a three-bedroomed semi2 informalDS a semi-final3 American EnglishTTR a very large heavy truck consisting of two connected parts, which carries goods over long distances SYN articulated lorry British English
Examples from the Corpus
semi• Outside, the once-respectable semis have crooked To Let signs and greying net curtains.• Phebus beat Stanford's Ania Blezynski in the semis.• Leicester won their semi against Gloucester 19-15.semi-semi- /semi/ prefix 1 XXexactly half a semicircle2 PARTLYpartly but not completely in the semi-darkness semi-literate people3 XXhappening, appearing etc twice in a particular period a semi-weekly visit a semi-annual publication → bi-Examples from the Corpus
semi-• a semi-invalidFrom Longman Business Dictionarysemi-semi- /semi/ prefix1used to show that something happens, appears etc twice in a particular period of timeWe hold a semi-weekly meeting for all team leaders.2used to show that something is partly but not completely doneRaw materials andsemi-finished goods rose 0.6%.He describes himself as semi-retired, but remains on several boards.Origin semi 1. (1900-2000) semi-detached2. (1900-2000) semi-final3. (1900-2000) semi-trailer semi- Latin 