"A field officer, field-grade officer, or senior officer is an Army, Marine, or Air Force commissioned officer senior in rank to a company officer but junior to a general officer. In most armies this corresponds to the ranks of major, lieutenant colonel and colonel, or their equivalents. Some countries also include brigadier in the definition.
Historically, a regiment or battalion´s field officers made up its command element." - (en.wikipedia.org 06.03.2022)
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