brash

a.

  1. Hasty in temper; impetuous.
  2. Brittle, as wood or vegetables.

n.

  1. A rash or eruption; a sudden or transient fit of sickness.
  2. Refuse boughs of trees; also, the clippings of hedges.
  3. Broken and angular fragments of rocks underlying alluvial deposits.
  4. Broken fragments of ice.