Plural of “court-martial”

The plural of court-martial is courts-martial (some dictionaries also accept court-martials).

Why

"Court-martial" follows French noun-adjective word order, with "court" as the head noun and "martial" (meaning military, from Mars, the Roman god of war) functioning as a descriptive adjective placed after it, exactly as French grammar requires but English ordinarily does not. Because "court" is the true head noun being counted, the plural -s belongs there, giving "courts-martial" rather than "court-martials."

This French-derived word order survives in English almost exclusively within a small cluster of formal legal and governmental titles, "attorney general," "notary public," and "court martial" among them, all borrowed directly from Anglo-Norman legal French during a period when French remained the dominant language of English law and government administration for several centuries after the Norman Conquest. Even so, "court-martials" turns up often enough in everyday and military-adjacent journalism, a sign that many writers no longer consciously parse "martial" as a trailing French adjective and simply tack the plural onto the end the way they would with any ordinary English word.

Usage note

"Courts-martial" remains the standard, formally correct plural in military law, legal writing, and careful journalism ("the military convened three separate courts-martial"). "Court-martials" appears often enough in casual and even some professional writing that it won't universally read as wrong, but military legal documents and style guides still generally expect "courts-martial."

"Court-martial" also functions as a verb ("the soldier was court-martialed"), and in that verb form the past tense simply adds -ed to the very end of the whole compound, a spelling that looks inconsistent with the noun's own pluralization rule but is in fact entirely standard, since verb conjugation and noun pluralization follow separate grammatical rules even within the same compound word. Military justice systems worldwide maintain their own distinct court-martial procedures, and comparative military law scholarship often discusses how "courts-martial" differ structurally between countries, including differences in whether officers or enlisted personnel serve on the panel deciding a case.

Common real mistakes

Writers reach for "court-martials" far more often than the correct form, missing the fact that "court" is the noun actually being pluralized rather than the whole fixed phrase. It's also worth keeping this military tribunal separate in your mind from the everyday civilian "court," which pluralizes as a completely ordinary noun, "courts," free of any of the French-derived quirks that shape its military cousin.

The wider pattern

The identical logic, noun first, adjective trailing, plural marker on the noun, also governs "attorney general" ("attorneys-general") and "notary public" ("notaries public"); all three titles were borrowed together from the same body of Anglo-Norman legal vocabulary and none of them pluralize at the very end of the phrase the way an ordinary English compound would.

Examples

• Three separate courts-martial were convened after the incident.
• The military justice system handled several courts-martial that year.
• Both courts-martial ended in convictions.
• Historians studied courts-martial from the Second World War for the documentary.
• The base commander ordered courts-martial for the two officers involved.
• Several high-profile courts-martial drew national media attention.
• The defense attorney had handled dozens of courts-martial over his career.
• Records of past courts-martial are kept in military archives.
• The panel reviewed courts-martial from three different branches of service.
• Multiple courts-martial resulted from the same chain of command failure.
• The general reviewed the findings of both courts-martial personally.
• Legal scholars compared courts-martial procedures across different eras.
• The documentary examined controversial courts-martial from the war.
• The two courts-martial reached very different verdicts.
• Military historians catalogued courts-martial from the entire campaign.
• The appeals process reviewed both courts-martial for procedural errors.
• Both courts-martial were held on the same military base.
• The lawyer specialized in defending soldiers facing courts-martial.
• The unit's history included several notable courts-martial.
• The report summarized every court-martial held that fiscal year.
• The archive holds transcripts from dozens of past courts-martial.