brassening

Verb

brassen (third-person singular simple present brassens, present participle brassening, simple past and past participle brassened)

1. (ambitransitive) To make like or become like brass, particularly in fortitude or colour
   • He could possibly understand a man wishing to blacken the gray as he aged, it was only natural—to a point, and then it was not. But to brassen one's hair like a homosexual?2004, Tom Morrisey, Deep Blue, page 290