L Syrett and K Nuthall, Renewable diesel growth set to disrupt liquid fuel markets, Energy World, December 2021, p 26

In the diesel-fuel world, a distinction is drawn between:

Biodiesel.   Lipids from plant-based oils or recycled restaurant grease go through transesterification with alcohols, being known as FAME in USA and RME in Europe.   Because of the oxygen content, it cannot be used as a drop-in with fossil diesel, and blends are limited to B20.

Renewable diesel.   Derived from the more plentiful organic wastes which are purified and then hydrotreated at a high temperature to remove triglycerols (fats), metals, plus oxygen and nitrogen compounds.    It is usable down to -34°C, and can be blended up to 100%.