This is the 775th most frequent Hindi word.
not
The Hindi word "not" does not exist; it might be a transliteration of the English word "not." If referring to "नोट" (not in Hindi), it means "note" (a written message or currency).
Here 'नहीं' is used as a negation to indicate that the action of drinking tea did not occur.
मैंने चाय नहीं पी।
I did not drink tea.
In this sentence, 'नहीं' negates the possessive context, indicating that the pen does not belong to the speaker.
यह पेन मेरा नहीं है।
This pen is not mine.
Here, 'नहीं' negates the state of knowing, indicating lack of knowledge.