The important bit first. In the US spelling - Pseudonymization - with the z scores over 30 in scrabble.

Now the bit I struggle to understand:

Pseudonymization is a data management and de-identification procedure by which personally identifiable information fields within a data record are replaced by one or more artificial identifiers, or pseudonyms.[1] A single pseudonym for each replaced field or collection of replaced fields makes the data record less identifiable while remaining suitable for data analysis and data processing.

Its great to see how much easier computerisation has made our lives