'Ordinance' is a local law or municipal regulation; 'ordnance' refers to military weapons, ammunition, and artillery.
Noun. A law, decree, or regulation passed by a local authority such as a city council or municipality.
The city passed an ordinance banning the use of single-use plastic bags at retail stores.
Local ordinances require noise levels to fall below 65 decibels after 10 p.m.
Violating the parking ordinance results in a fine of up to two hundred dollars.
Noun. Military weapons, ammunition, and artillery collectively. Also: a branch of the armed forces that supplies and maintains weapons. Note: 'unexploded ordnance' (UXO) is a common technical term.
The army's ordnance team was called in to safely dispose of the unexploded shells.
Significant quantities of unexploded ordnance from World War II are still found in Europe today.
The ordnance depot was secured against unauthorised access with multiple layers of physical protection.
Common mistake
"The municipality passed new ordnance" when meaning regulation (correct: ordinance). Or "They discovered ordinance near the beach" when meaning unexploded weapons (correct: ordnance). The I in 'ordInance' is the key: the law has an extra I; the weapon does not.
Trick to remember it
'OrdInance' has an I like 'cIty law' — it is a civil regulation. 'Ordnance' drops the I — military equipment is stripped down to essentials, no extra letters.
Quick rule
Is it a local law or regulation? 'OrdinAnce' (with I). Is it military weapons or ammunition? 'Ordnance' (no I).
Did you know?
The UK's Ordnance Survey (founded 1791) is named after the Board of Ordnance — the military body that created it to map Britain for defence against potential Napoleonic invasion. Its maps are considered among the most precise national cartographic products in the world. 'Unexploded ordnance' (UXO) remains a genuine public safety issue across Europe, the Middle East, and Southeast Asia, where World War II and 20th-century conflicts left millions of explosive devices in the ground. Belgium, for instance, still recovers thousands of pieces of WWI ordnance each year through its 'Iron Harvest'.
Exercise 1 · Pick the right one
The disposal team was deployed to safely neutralise the unexploded _____ found near the construction site.
Exercise 2 · Pick the right one
The _____ passed last month restricts short-term rentals in residential neighbourhoods.
Exercise 3 · Form the word
Is it a local law or regulation? 'OrdinAnce' (with I). Is it military weapons or ammunition? 'Ordnance' (no I).
"The municipality passed new ordnance" when meaning regulation (correct: ordinance). Or "They discovered ordinance near the beach" when meaning unexploded weapons (correct: ordnance). The I in 'ordInance' is the key: the law has an extra I; the weapon does not.
'OrdInance' has an I like 'cIty law' — it is a civil regulation. 'Ordnance' drops the I — military equipment is stripped down to essentials, no extra letters.
Bryan López
Founder of SpeakUP Academy