Refers to a skilled technical worker, often in fields like engineering, IT, audio, or laboratory work. Usage is similar to English.
彼は音響のテクニシャンとして働いている。
He works as a sound technician.
テクニシャンが機械の修理に来た。
A technician came to repair the machine.
He is known as a technician (skilled player) in soccer.
She is known as a technician (virtuoso) on the piano.