EU Law:

Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on waste and repealing certain Directives (Text with EEA relevance)
Consolidated version as 18/02/2024 at https://eur-lex.europa.eu/legal-content/EN/AUTO/?uri=CELEX:02008L0098-20240218

Pre-consumer material is defined in standards ISO 472, ISO 14021:2016, EN 45557:2019

Post-consumer material is defined in standards ISO 472: 2013 (confirmed 2018), ISO 14021: 2016, EN 45557:2019

“Waste” is defined differently by EU Law and Standards.

An important distinction between the terminology used in legally binding EU law, and in non binding international guidelines and standards, is that the latter define ‘waste’ only when ‘waste’ cannot exercise any further functions and cannot be recovered, in all the other cases
the preferred terminology is ‘material’.
As ‘pre-consumer’ and ‘post-consumer material’ are not included within the EU legal framework, there are no legally binding definitions for these

The distinct definitions are 

• EU Law “Waste” means any substance or object which the holder discards or intends or is required to discard.
  Examples of waste (EU Law): Agricultural waste, Packaging waste, Municipal waste, Waste Electrical and Electronic Equipment (WEEE), End-of-life vehicles (ELV).

• by Standards: “Waste” is something that can no longer be used for its intended purpose or for any other purpose, i.e., it cannot be re-processed or re-used.

  • Pre-consumer material
    Material derived from a manufacturing process’s waste stream and reintroduced within the same process (e.g., rework, regrind, scrap).

  • Once it can no longer be used for its intended purpose, it is considered post-consumer waste. This also includes returns of material from the distribution chain.

  • Post-consumer material
    Material generated by households or by commercial, industrial, or institutional facilities in their role as end-users of a product.