- noun an officer in the army or marines (ranking above a lieutenant-colonel and below a brigadier, usually employed as a senior staff officer).
- noun an officer in the army, marines or air force (usually in command of a regiment or equivalent-sized grouping or employed as a senior staff officer).
Origin & History of “colonel”
Historically, a colonel was so called because he commanded the company at the head of a regiment, known in Italian as the compagna colonnella, literally the ‘little-column company’; hence the commander himself took the title colonnella. The word colonnella is a diminutive form of colonna, which is descended from Latin columna ‘pillar’ (source of English column). It appears first to have entered English via French in the form coronel, in which the first l had mutated to r. Spellings with this r occur in English from the 17th and 18th centuries, and it is the source of the word’s modern pronunciation. Colonel represents a return to the original Italian spelling.