apostrophe: possession

The primary use of the apostrophe is to indicate possession. A word which does not end in a sibilant (s or z sound) forms the possessive by the addition of ’s:

• a dog’s breakfast
• Toronto’s CN Tower

Note that it is the pronunciation, not the spelling, which determines the possessive form. The word conscience ends in a sibilant; Illinois does not.

To form the possessive of French words ending in a non-sibilant s or x, add an ’s:

• Duplessis’s cabinet
• Malraux’s art

Regarding the appropriate form for singular words that end in a sibilant, pronunciation is again the determining factor. If it would be natural to pronounce an extra s, add ’s; if an additional s would be difficult to pronounce, add only an apostrophe:

• Joyce’s Ulysses
• Ulysses’ wanderings
• Brussels’ bureaucrats
• the boss’s office

Since awkwardness of pronunciation is the basic criterion, the decision to add or omit a possessive s ultimately depends on the writer’s own sensitivities. One option is to rephrase:

• the tourist industry of Mauritius
• the ramblings of Joyce’s Ulysses

rather than

• Mauritius’ tourist industry
• Joyce’s Ulysses’ ramblings

Plural possessives

Plural forms which do not end in a sibilant are no exception to the general rule:

• women’s
• children’s

Plurals ending in a sibilant (that is, most plurals) take only the apostrophe:

• the ministers’ responsibilities
• developing countries’ needs

Inanimate possessors

With inanimate "possessors" (in particular, abstract concepts), the apostrophe is generally not used to denote possession. Use an "of" construction instead:

• the incidence of conjugal violence
• the priority of tourism

not

• conjugal violence’s incidence
• tourism’s priority

However, certain expressions of time and measurement do take the apostrophe:

• a month’s vacation
• ten dollars’ worth

Compounds

Figurative compounds of the sort bull’s-eye or crow’s-nest retain ’s in the plural:

• bull’s-eyes
• crow’s-nests
• shepherd’s pies

When the possessive of a compound noun or a noun phrase is formed, add ’s to the last word only, unless there is a possessive relation between the words within the phrase itself:

• someone else’s problem
• her brother-in-law’s address

but

• John’s father’s problem

Two nouns (group genitive)

If possession is shared by two or more subjects, add ’s to the last word only:

• Adam and Eve’s progeny
• the Prince and Princess’s visit
• Rodgers and Hammerstein’s musicals

To indicate individual possession, ’s is added to each element in the series:

• Abraham’s and Lot’s descendants
• Rodgers’ and Hammerstein’s private lives

Geographical names

The apostrophe is often omitted in geographical names:

• Gods Lake
• Humphreys Mills

but

• St. John’s
• Land’s End

Note also Saint John (city in New Brunswick) and Hudson Bay—but Hudson’s Bay Co. Consult the Gazetteer of Canada when in doubt.

Institutions and organizations

The ’s is often omitted in names of institutions, especially in the case of plural nouns that are adjectival rather than strictly possessive:

• teachers college but inmates’ committee
• veterans hospital but officers’ mess

The official or customary form should be used, whatever it may be:

• Timothy’s
• Canadian Forces Headquarters

Its

Note that there is no apostrophe in the possessive forms yours, hers and its. It’s is always a contraction of it is.

© Public Services and Procurement Canada, 2024
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