n.
In construction, the systematic arrangement of bricks or other building units (e.g., concrete blocks, glass blocks, or clay tiles) to ensure stability.
Units laid with their ends toward the face of a wall are called headers; units with their lengths parallel to the wall are called stretchers. Common types are the English bond (courses of stretchers and headers alternate), the Flemish or Dutch bond (headers and stretchers are laid alternately within each course, each header being centered over the stretcher below it), and the American bond (every fifth or sixth course consists of headers, the rest being stretchers). See also masonry .