NVOCC (Non-Vessel Operating Common Carrier)
An ocean carrier that does not own ships but buys container space from shipping lines, issues its own bills of lading, and resells transport.
TL;DR: An NVOCC is a company that acts as a carrier for ocean shipments without operating any vessels. It buys container space from shipping lines and issues its own house bill of lading to the shipper.
The term comes from US shipping regulation, where NVOCCs are licensed or registered with the Federal Maritime Commission, but the business model exists worldwide. To the actual shipping line, the NVOCC is the shipper. To you, the NVOCC is the carrier. This creates two layers of documents: the master bill of lading from the shipping line to the NVOCC, and the house bill of lading from the NVOCC to the shipper. See MBL and HBL.
NVOCCs are especially common for LCL cargo. They consolidate many small shipments into one container, ship it under their own contract, and then separate the cargo at the destination warehouse. This is what makes small sea shipments possible at a reasonable cost.
The difference from a plain Freight Forwarder is liability. A forwarder may only arrange transport as an agent, while an NVOCC takes on carrier responsibility under its own bill of lading. In practice, many companies act as both.
When your shipment moves under a house bill of lading, the cargo is released at destination by the NVOCC or its local agent, not directly by the shipping line. Ask your forwarder who the destination agent is and what local charges apply, so there are no surprises when you collect your goods.