Ordinance vs. Ordnance: Law or Weapons?

The Distinction

• Ordinance = a law or regulation, especially a municipal one
• Ordnance = military weapons, ammunition, and equipment

Using Ordinance

“Ordinance” refers to official rules or laws:

• “The city passed a new parking ordinance.” ✓
• “The ordinance prohibits loud noise after 10 PM.” ✓
• “Local ordinances vary by jurisdiction.” ✓
• “The zoning ordinance affects new construction.” ✓

Using Ordnance

“Ordnance” refers to military supplies:

• “The army stored ordnance at the depot.” ✓
• “Unexploded ordnance remains a danger in the region.” ✓
• “The ordnance survey mapped the terrain.” ✓ (British mapping agency, originally military)
• “Heavy ordnance was deployed during the battle.” ✓

Memory Trick

• Ordinance = has an I for “I must follow the law”
• Ordnance = no I, because weapons don’t care about you

Or:

• Ordinance = think “ordinary laws” (local regulations)
• Ordnance = think “arms” (military equipment—no I in arms)

Quick Check

Talking about laws or regulations? → ordinance Talking about military weapons? → ordnance