Re: EU? By who's definition?
Yes, DPA 2018 has indeed been modified by subsequent legislation, e.g. The Data Protection, Privacy and Electronic Communications (Amendments etc) (EU Exit) Regulations 2019 (https://www.legislation.gov.uk/uksi/2019/419/contents). For several years they let the text of the DPA languish, but the one there now is current - https://www.legislation.gov.uk/ukpga/2018/12/contents - including the UK GDPR.