Asterism.

In Astronomy, an asterism is a remarkable figure drawn by particularly brilliant stars.   Complete Pdf by my website.

In general, these stars are not linked by either a significant gravitational interaction or a common gestation, which makes an asterism a rather arbitrary and subjective celestial object.

It is often on the basis of asterisms that civilizations have imagined their constellations, although an asterism could as well form a part of a constellation as being made up of stars belonging to several different constellations.