This informal sports use refers to a semifinal, the round immediately before a final.
The team reached the semis.
She lost in the semi by one point.
This mainly North American meaning refers to a large truck consisting of a tractor and semitrailer, or sometimes the trailer itself.
A semi blocked one lane of the highway.
The driver parked the semi beside the warehouse.
This British informal meaning refers to a house joined to one other house by a shared wall.
They bought a semi in the suburbs.
The street is lined with red-brick semis.
This meaning refers to the prefix semi-, used to indicate half, partial condition, incomplete degree, or partial resemblance.
Semi- means partly in the word semiconscious.
A semicircle is half of a circle.
In some time expressions, semi- means occurring twice within the named period rather than half of it.
Semiannual means occurring twice each year.
The company issues a semiweekly report.