Port Trunking on EnGenius allows you to assign physical links to one
logical link that functions as a single, higher-speed link, providing
dramatically increased bandwidth. You can use Port Trunking to bundle
multiple connections and use the combined bandwidth as if it were a single
larger “pipe”. Do not confuse yourself with Cisco's
port trunking and EnGenius' port trunking. Cisco's port trunking
refers to port tagging for VLAN on a certain port. 

"Port Trunking" can be accessed by going to L2 Features>Link
Aggregation on your EnGenius device' user interface.