expression
right in front of one's nose; right next to you
Used for something physically very close, often with a nuance of being so close it's almost touching or obvious.
答えは鼻の先にあったのに、気づかなかった。
The answer was right under my nose, but I didn't notice.
彼は鼻の先でタバコの煙を吐き出した。
He blew cigarette smoke right in front of my nose.
expression
tip of one's nose
Literal body part meaning; less common than the idiomatic sense.
寒さで鼻の先が赤くなった。
The tip of my nose turned red from the cold.