A singular noun in Klingon has no specific suffix indicating that it is singular: nuH ("weapon") refers to a single weapon of any type. However the absence of a plural suffix does not always mean the noun is singular. In Klingon, a noun without a plural suffix may still refer to more than one entity. The plurality is often indicated by a pronoun—either a verb prefix (see section 4.1), a full pronoun (section 5.1), or simply by context.

For example, yaS ("officer") can refer to a single officer or a group of officers, depending on other words in the sentence:

• yaS vImojpu' – I became an officer.
• yaS DImojpu' – We became officers.
• yaS jIH – I am an officer.
• yaS maH – We are officers.

In the first pair, the verb prefixes (vI- for "I", DI- for "we") signal number. In the second pair, the subject pronouns (jIH for "I", maH for "we") provide that information.

Sometimes, only context clarifies whether a noun is singular or plural. For instance, yaS mojpu' could mean "he/she became an officer" or "they became officers", depending on what the speaker and listener already know.

Fortunately, it is never incorrect to explicitly mark a noun as plural using a plural suffix. Both yaS maH and yaSpu' maH ("we are officers") are grammatically correct. However, you cannot add a plural suffix to a noun referring to only one thing. The sentence yaSpu' jIH ("I am officers") is incorrect in Klingon.

Klingon uses three plural suffixes, depending on the type of noun:

-pu' (plural for beings capable of using language)

This suffix is used for people and other intelligent beings.

• yaS – officer → yaSpu' – officers
• Duy – emissary → Duypu' – emissaries

-Du' (plural for body parts)

This suffix is used exclusively for body parts, regardless of the type of creature.

• qam – foot → qamDu' – feet
• tlhon – nostril → tlhonDu' – nostrils

-mey (general plural)

This suffix is used for non-speaking beings, inanimate objects, and abstract nouns. It may also be used with speaking beings to add a sense of "scattered all about."

• mID – colony → mIDmey – colonies
• yuQ – planet → yuQmey – planets
• puq – child → puqmey – children (scattered everywhere)

The suffix -mey cannot be used with body parts. However, Klingon poets may violate this rule for stylistic effect—for example, tlhonmey (nostrils scattered about). Until you understand such poetic nuances, stick to the grammatical rule.

Inherently Plural Nouns

Some Klingon nouns are always plural and never take plural suffixes:

• ray' – targets
• cha – torpedoes
• chuyDaH – thrusters

These have distinct singular counterparts:

• DoS – target
• peng – torpedo
• vIj – thruster

The singular forms can take -mey, but this implies a scattered or disorganized arrangement:

• DoSmey – targets scattered all about
• pengmey – torpedoes all over the place

Even though inherently plural nouns like cha are conceptually plural, they are treated grammatically as singular nouns. For example:

• cha yIghuS – Stand by torpedoes! (Note: yI- is the singular imperative prefix)