Glue Network

I heard this term used instead of “Transit VLAN”

Transit VLAN

A transit VLAN is a small network range that sits between two routers/firewalls which connect two environments together, where the two environments do not belong to the same organisation. As they do not belong to the same organisation neither router/firewall can have an IP from the other organisations IP range, so the transit VLAN sits between the two routers as a neutral network space.