Words ending in -ary, -ory, and -ery

It can be difficult to know which of these endings is correct. Here are a few general tips:

Words ending in -ary

• Words ending in -ary can be nouns (e.g. boundary, anniversary), adjectives (e.g. ordinary, customary), or both (e.g. contemporary, subsidiary).
• If the part of the word before the ending isn't a recognizable English word in itself, then it's often (but not always!) the case that the ending will be -ary (e.g. vocabulary, library).

Here are some common words that end in -ary:

arbitrary; disciplinary; dictionary; solitary; extraordinary; adversary; secretary; stationary; necessary; beneficiary; summary; temporary; commentary; voluntary; imaginary; honorary; visionary; complimentary; reactionary; intermediary; secondary;  itinerary.

Words ending in -ory

• Words ending in -ory can be nouns (e.g. category, lavatory) or adjectives (e.g. derogatory, satisfactory).
• They're sometimes related to nouns ending in -or. For example: contributory (from contributor) and rectory (from rector).
• Many words ending in -ory are related to English words ending in -ion. For example: introductory (from introduction) and preparatory (from preparation).

Here are some common words that end in -ory:

accessory; derisory; promontory; advisory; inventory; laboratory; depository; inflammatory;  directory; conservatory; mandatory; sensory; contradictory; explanatory; memory; factory; territory; history; victory; predatory; theory.

Words ending in -ery

• Words ending in -ery are nearly always nouns and they're often related to words ending in -er. For example: brewery (from brewer) and machinery (from machine).
• As well as nouns, there are some adjectives that end in -ery, and they are also mostly based on words that end in -er (e.g. blustery, shivery).
• If the part of the word before the ending is a recognizable English word in itself, then it's often (but not always!) the case that the ending will be -ery. For example: mockery (from mock) and trickery (from trick). This is also true when the base word ends in an e that's dropped before the -ery ending is added (e.g. brave; bravery or forge; forgery) or where it ends in a consonant that's doubled when the ending is added (e.g. distil; distillery or rob; robbery).

Here are some common words ending in -ery:

gallery; nursery; cemetery; slippery; jewellery; feathery; crockery; lottery; celery; pottery; recovery; cutlery; bakery; delivery; discovery; artery; scenery; battery; misery;  flattery; stationery; surgery; monastery; snobbery; mystery.