A fellow soldier or a companion in arms; someone serving in the same military force or cause.
From Latin commilitans, from com- ('with') + miles ('soldier'). This term was more common in English during the 17th-18th centuries when military life and terminology were more prominent in literature.
The word 'commilitant' reveals how soldiers of the same unit bonded so deeply that a specific term was needed — it's more personal than 'fellow soldier,' implying shared danger and trust.
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