In short, an FSRU is a Liquefied Natural Gas (LNG) storage ship that has an onboard regassification plant capable of returning LNG back into a gaseous state and then supplying it directly into the gas network.

The FSRU Explorer – Fit for the Future
In short, an FSRU is a Liquefied Natural Gas (LNG) storage ship that has an onboard regassification plant capable of returning LNG back into a gaseous state and then supplying it directly into the gas network.