black ash

noun

Definition of black ash

1 : a North American ash (Fraxinus nigra) having dark brown heavy wood — called also basket ash, brown ash, hoop ash

2 : an Australian eucalyptus (Eucalyptus stellulata)

3 : box elder

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Origin and Etymology of black ash

ash (tree)

black ash

noun

Definition of black ash

1 : any of various dark-colored crude products obtained in industrial processes: such as

a : crude sodium carbonate obtained in the Leblanc process

b : crude barium sulfide

2 : a black mass containing chiefly soda in the form of sodium carbonate and usually also sodium sulfide with some carbon and produced especially for recovery of its soda content by concentrating and burning black liquor (see black liquor 2) in rotary furnaces