D defs.my
Entry 3 senses Webster, 1913

Saturation

/săchˌ-ẽr-āsh'-ən/ · Sat·u·ra·tion · IPA /sˌætʃərˈeɪʃən/
01 n. The act of saturating, or the state of being saturating; complete penetration or impregnation.
  1. 1.
    The act of saturating, or the state of being saturating; complete penetration or impregnation.
  2. 2.
    The act, process, or result of saturating a substance, or of combining it to its fullest extent.(Chem.)
  3. 3.
    Freedom from mixture or dilution with white; purity; -- said of colors.(Optics)