Common Words:
* Midday: The middle of the day.
* Midweek: The middle of the week.
* Midterm: A test given in the middle of a term.
* Midnight: The middle of the night.
* Middle: The center point.
* Midland: An area in the middle of a country.
* Midpoint: The point halfway between two points.
Less Common Words:
* Midcourse: In the middle of a course or journey.
* Midstream: In the middle of a stream.
* Midsummer: The middle of summer.
* Midwinter: The middle of winter.
* Midrange: The middle range of something.
* Midriff: The part of the body between the chest and the waist.
* Mid-air: In the middle of the air.
* Mid-ocean: In the middle of the ocean.
* Mid-August: In the middle of August.
Prefix "mid-" is usually used to mean "in the middle of" or "halfway through".