What this suffix does
-ory forms two types of words: adjectives meaning "relating to" or "required" (mandatory, laudatory, contradictory), and nouns naming a place (dormitory, laboratory, purgatory).
ESEN
Suffix · forms adjectives
-ory
Forms adjectives that mean "relating to" or "mandatory" (mandatory, contradictory) and nouns naming a place (dormitory, laboratory).
In Spanish: -orio / relativo aIntermediate
Written by Bryan López, English teacher · Updated
Trap: laudatory vs derogatory
"laudatory" (praising, positive) and "derogatory" (insulting, negative) sound similar but mean the opposite. A laudatory comment praises you; a derogatory one insults you.
How it is formed
Latin root + ory. Produces adjectives (relating to) or nouns (place/instrument for).
- adjective: relating to / serving formandat- = mandatorylaud- = laudatorycontradict- = contradictorypromiss- = promissorypreparat- = preparatoryinflamm- = inflammatory
- noun: place fordormir- (sleep) = dormitoryaudit- (hear) = auditory/auditoriumlaborat- (work) = laboratoryconservat- = conservatoryorat- (speak) = oratory
- noun: literary/theologicalpurgat- (purge) = purgatorypromontori- = promontorytrajectori- = trajectorycategori- = category
In British English: "laboratory" = /ləˈbɒrətri/ (stress on second syllable). In American English: /ˈlæbrətɔːri/ (stress on first). This is one of the most famous British/American pronunciation differences.
How it is pronounced
-ory/ɔːri/ · rhymes with glory
Tap the button to hear how the ending sounds. Each word in the table has its own audio.
Examples
Base word
With -ory
In a phrase
- mandatemandatoryWearing a seatbelt is mandatory in this country.
- laud (praise)laudatoryThe article was laudatory, praising the team's hard work.
- promisepromissoryHe signed a promissory note to repay the loan.
- contradictcontradictoryThe two witnesses gave contradictory accounts of the accident.
- purgepurgatoryWaiting at the DMV all afternoon felt like purgatory.
- preparepreparatoryThe class is a preparatory course for the exam.
- orate (speak)oratoryHer oratory skills impressed the whole room.
- dormir (sleep)dormitoryMost first-year students live in the dormitory.
- audit (hear)auditoryThe test checks both visual and auditory memory.
- promonto- (headland)promontoryThe lighthouse sits on a rocky promontory above the sea.
Common mistakes
laudatory = derogatory (both end in -atory)
laudatory = expressing praise (positive); derogatory = expressing disrespect (negative)
"laudatory" = praising, complimentary: "laudatory remarks about her work." "derogatory" = disrespectful, belittling: "derogatory comments." They are near-antonyms. Both end in -atory but have opposite meanings. Very common confusion.
mandatory = recommended (strong suggestion)
mandatory = compulsory, legally required, not optional
"mandatory" = required by law, rule, or authority. Not optional. "mandatory sentencing" = the judge must apply the sentence, no discretion. "Mandatory evacuation." This is much stronger than "recommended" or "advised."
A trick to remember it
Picture a building with rooms named in -ory: the dormitory next to the laboratory. For the adjectives, picture an order that must be obeyed: mandatory comes from "to mandate", required by order.
Practise what you learned
Exercise 1 · Pick the right one
"Laudatory" and "derogatory" are...
Exercise 2 · Form the word
Exercise 3 · Pick the right one
How is "laboratory" pronounced in British English?
Frequently asked questions
What does the suffix -ory mean in English?
The suffix -ory forms adjectives that mean "relating to" or "mandatory" (mandatory, contradictory) and nouns naming a place (dormitory, laboratory). In Spanish it usually maps to -orio / relativo a.
How do you pronounce -ory?
The ending -ory is pronounced /ɔːri/ · rhymes with glory. For example, "mandatory".
Can you give an example of a word with -ory?
"mandate" becomes "mandatory". It is a typical example of the -ory suffix.
Other useful suffixes
-age
Names a collective action, process or result: dam becomes damage.
-ery / -ry
From Old French "-erie": forms nouns of activity, place, collective quality or state. Chivalry, trickery, wizardry, bravery, mockery.
-ian / -ean
Turns proper nouns into style or period adjectives: Orwellian = relating to Orwell's ideas of surveillance and totalitarianism.
Learn every English suffix
-tion, -ness, -ful, -ly, -able... every ending you need to understand thousands of words at once.