A physical association whereby two Entities are in some (even lose) spatial relationship with each other such that they touch each other in some way.

Examples: the colon is connected (and therefore adjacent) to the jejunum; the colon is adjacent to the liver (even if not actually connected.)

UsageConstraints: Adjacency is in principle a symmetrical connection, but scoper and player of the role should, where applicable, be assigned to have scoper be the larger, more central Entity and player the smaller, more distant, appendage.

An adjacency of two Entities held together by a bond which attaches to each of the two entities.

Examples: biceps brachii muscle connected to the radius bone, port 3 on a network switch connected to port 5 on a patch panel.

UsageConstraints: See Adjacency for the assignment of scoper (larger, more central) and player (smaller, more distant).

A connection between two atoms of a molecule.

Examples: double bond between first and second C in ethane, peptide bond between two amino-acid, disulfide bridge between two proteins, chelate and ion associations, even the much weaker van-der-Waals bonds can be considered molecular bonds.

UsageConstraints: See connection and adjacency for the assignment of player and scoper.

A connection between two regional parts.

Examples: the connection between ascending aorta and the aortic arc, connection between descending colon and sigmoid.

UsageConstraints: See connection and adjacency for the assignment of player and scoper.