Ancestor shared by multiple descendants.

Reverence for deceased family members.

In kinship and descent, a common ancestor from whom a lineage or clan may trace its descent. The ancestor who is at the apex of the genealogy.

In graph theory and computer science, the lowest common ancestor (also called least common ancestor) of two nodes and in a tree or directed acyclic graph is the lowest (i.e. deepest) node that has both and as descendants, where we define each node to be a descendant of itself (so if has a direct connection from , is the lowest common ancestor).

The last universal common ancestor is the hypothesized common ancestral cell from which the three domains of life, the Bacteria, the Archaea, and the Eukarya originated.

In biology and genetic genealogy, the most recent common ancestor, also known as the last common ancestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended.

Chinese ancestor veneration, also called Chinese ancestor worship, is an aspect of the Chinese traditional religion which revolves around the ritual celebration of the deified ancestors and tutelary deities of people with the same surname organised into lineage societies in ancestral shrines.