In modern Chinese 铣 is a technical machining term, 铣床 (milling machine), 铣刀 (milling cutter). It rarely stands alone outside the workshop.
history
An older reading 铣 meant 'shining metal', and in telegrams it once stood for the 16th of the month, both senses are now obsolete. The phonetic 先 also drives 洗 and 跣.