x1 is an entity in a dynamical system/scenario x2 which exhibits (possibly emergent) biological-like properties/phenomena x3
x1 need not be alive or actually 'biological'. Such properties include certain responses/behaviors in (for example: game theoretic) scenarios, Darwinistic evolution, a tendency toward self-perpetuation or proliferation, population dynamics, etc. Ideas, human organizations and businesses, biological populations, automata (such as in Conway's Game of Life), individual people, etc. demonstrate this feature.