Definitions for "Breast height"
Keywords:  uphill, girth, diameter, metres, height
4V2 ft above ground level. See d.b.h.
Almost universally adopted as the standard height for measuring girth, diameter and basal area of standing trees. In India, Burma, America, Union of South Africa, Malaya and some other British Colonies, it is taken at 4 feet 6 inches (1.37 m.) above ground level. Europe, U.K. and most other countries of the Commonwealth have it as 4 feet 3 inches (1.30 m.) and this is recommended as a standard for international adherence by FAO. Abbr. b.h. On slopes, breast height is taken on the uphill side. ( BCFT modif.).
The standard height at which the diameter of the stem of a standing tree is measured: 1.3 metres above ground level. By international agreement (through the International Union of Forest Research Organizations), 1.3 m from ground level, at which height the girth or diameter of trees are commonly measured. (Note: l.37 m is used in some parts of the world.)
a wall, chest high, from behind which musketry fire could be directed against an approaching army.