Meanings of alternate course in English

Something that could become an alternate course at minimum notice.

Give me full Dirac on all circuits, and have our alternate course ready to plug in.

In either case, at the corners, a quarter-brick called a closer has to be used in each alternate course to complete the breaking joint.

Moreover, every alternate course was cross-pinned, and the workman was rapidly becoming asphyxiated by the terrible reek which came billowing in from the chamber beyond.

The banquets thereafter were made up of alternating courses of Chinese and foreign food.

The order of alternating course was determined by the time of entry into the study.

Opposition forces may compel the squads to fall back on one of their alternate courses of action.

Where do we meet with instances where long and short blocks of ashlar masonry are disposed in alternate courses at the angles of walls?