steel-gray       
adjective uk/ˌstiːl ˈɡreɪ/ us/ˌstiːl ˈɡreɪ/
 深灰色的
of a dark grey colour 
  a steel-grey suit 一件深灰色的外套 
 - More examples
 - His steel-gray hair was neatly combed.
 - Thick flakes of snow were falling from a steel-gray sky.
 - She was a blonde, a natural blonde with steel-gray eyes.
 - The North Sea was steel-gray and choppy.
 - he steel-gray clouds that spanned the horizon