What is the meaning of Nikka?

A bowdlerization of nigga used as a reclaimed sense of nigger.

nod

bow

synonym of hikka (“hiccups”)

to make a slight movement with the head to greet someone or to point to something

to nod

to head, to strike a soccer ball with the head

accordion

Rōmaji transcription of にっか

inflection of nikke:

1. simple past
2. past participle

simple past

past participle

to nod (bow one's head)

to head (to play the ball with one's head)

Source: wiktionary.org