What is the meaning of -u?

masculine singular nominative and accusative suffixed definite article: the

out, outwards; used to modify verb direction

Used to form nouns from verbs.

ending used to form abstract nouns from adjectives (compare Modern English -ness), normally causing i-mutation, and remaining even when preceded by a long syllable

Used to form the first person singular present indicative of strong verbs and class I weak verbs

Used to form the nominative singular of short ō-stem nouns

Used to form the nominative and accusative singular of short u-stem nouns

Used to form the nominative and accusative plural of short a-stem and all ija-stem neuter nouns

Forms the strong nominative feminine singular and strong nominative/accusative neuter plural of adjectives

suffixed used to form adjectives (oblique masculine singular) from nouns

alternative form of -iu

Forms the indefinite accusative plural of masculine u-stem nouns.

Forms the indefinite dative singular of some ō-stem nouns and a few feminine consonant-stem and i-stem nouns, sometimes optionally.

Forms the indefinite accusative singular of a few ō-stem nouns, mainly personal names

Masculine singular agreement suffix

Masculine nominative/singular agreement suffix

volitive inflection of verbs, indicating that an action or state is desired, requested, ordered, or aimed for.

-one. (Ending of the individual correlatives.)

Derives nouns from verbs or prefixes

Forms nouns from verbs. Most common with e- and i-stem verbs.

Derives a number of nouns from other nouns.

forms adjectives having the sense of ‘having quality of, being provided with’ (the root word)

romanization of -𐌿

be

Added to a noun or a proper noun to form a diminutive.

indefinite accusative/dative/genitive singular of -a f (most weak feminine nouns)

inflection of -ur (most adjectives):

1. dative singular neuter strong
2. accusative/dative/genitive singular feminine weak
3. plural weak

dative singular neuter strong

accusative/dative/genitive singular feminine weak

plural weak

third-person plural past indicative/subjunctive of -a (strong verbs)

infinitive ending of two (preterite-present) modal verbs:

indefinite accusative and dative singular ending of some strong feminine nouns, especially those that end in -ing and female personal names

‎nótt (“night”) + ‎-u → ‎nóttu

‎sól (“sun”) + ‎-u → ‎sólu

indefinite accusative plural of -ur m (some strong masculine nouns); alternative form of -i

1. ‎sonur (“son”) + ‎-u → ‎sonu (“sons”)

   ‎sonur (“son”) + ‎-u → ‎sonu (“sons”)

   ‎vegur (“road, way”) + ‎-u → ‎vegu (“roads, ways”)

   ‎skjöldur (“shield”) + ‎-u → ‎skjöldu (“shields”)

   ‎stigur (“path”) + ‎-u → ‎stigu (“paths”)

   suffix used to form pronouns indicating a person

   to be (copula)

   Rōmaji transcription of う

   used to form nouns denoting action or result of action

   ablative/locative singular of -us for fourth-declension nouns.

   3rd-person masculine singular pronominal suffix: his, him

   Used in contractions with particles of possession to mean you

   Forms result or action nouns from verbs.

   Form of the suffix -i used with verbs in -ut.

   forms the masculine dative singular, now used to create adverbs, always used in conjunction with po

   forms the inanimate masculine genitive singular after soft or historically soft stems

   forms the masculine dative singular in certain words

   forms the masculine locative singular

   forms the masculine vocative singular

   forms the feminine vocative singular after -ś and -ź

   forms the neuter dative singular in soft and velar stems

   forms the neuter locative singular in soft and velar stems

   Form of -i after the vowels O / U.

   Form of -i after the vowels O / U.

   Form of -i after the vowels O / U.

   1. Derives nouns from verbs.

      Derives nouns from verbs.

      Forms verbnouns from verb stems.

      Source: wiktionary.org