What is the meaning of Yaku?

A condition that scores points when met, usually in the form of a specific combination of tiles or cards.

I

I (personal pronoun)

me (direct object of a verb)

me (object of a preposition)

me (indirect object of a verb)

I; me

I

I (personal pronoun)

me (direct object of a verb)

me (object of a preposition)

me (indirect object of a verb)

my (belonging to me)

I

I (personal pronoun)

alternative form of aku

wood

Rōmaji transcription of やく

Rōmaji transcription of ヤク

First-person singular absolutive independent pronoun; I, me

water

Source: wiktionary.org