(sem′ē) noun plural sem·is Colloq.
1. U.S. A semitrailer.
2. Brit. A semi–detached house.
—the semis Colloq. The semifinal round of competition in a sports competition.

1. Half; partly; not fully: semi–automatic, semicivilized.
2. Exactly half: semicircle.
3. Occurring twice (in the period specified): semiweekly. [<L]
Semi–, meaning not fully, partially, or partial, is found in solidemes and hyphemes, as in the list beginning at the foot of this page.