Bi-loaf 1 (or half bakery or loaf on loaf) is a still life that makes up half of a bakery (and is made up of two loaves). When the term bi-loaf is used, this pattern is its most common meaning.
There is a remarkable reaction where a glider collides with the bi-loaf, displacing it by (3,6) and generating another glider in the same direction as the incident glider. The only other known reactions of this type involve stable reflectors, which have a displacement of (0,0), alongside a constellation of three blocks. This displacement reaction has enabled the construction of half-baked knightships: