A designation is an administrative decision, published in a legal notice, that names a target and states the authority under which it is listed. In the United States it takes effect on publication in the Federal Register and simultaneous addition to the relevant OFAC list; in the EU it follows a Council decision and regulation; at the UN it follows a Security Council committee listing.
A designation entry is a structured record, not a sentence of prose. It carries the primary name, any aliases the authority is aware of, addresses, dates and places of birth or incorporation, identity document numbers, and the programme tag under which the listing was made. Those identifiers are what screening systems actually match against, which is why so much evasion effort goes into making a counterparty look like a name that is not on the list.