What does "deepen" mean?

Deepen: To make darker or more intense; to darken; as, the event deepened the prevailing gloom. You must deepen your colors. Peacham.

Additional senses

  1. 2.To make more poignant or affecting; to increase in degree; as, to deepen grief or sorrow.
  2. 3.To make more grave or low in tone; as, to deepen the tones of an organ. Deepens the murmur of the falling floods. Pope.
  3. 4.To become deeper; as, the water deepens at every cast of the lead; the plot deepens. His blood-red tresses deepening in the sun. Byron.

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