Noun
mesosystem (plural mesosystems)
A system of interconnections between the microsystems in an individual's life, such as interactions between a child's family and teachers.
The four systems are microsystem, mesosystem, exosystem, and macrosystem. Source: Internet
The mesosystem is the combination of two microsystems and how they influence each other (example: sibling relationships at home vs. peer relationships at school). Source: Internet