noun An older person who accompanies other younger people to ensure the propriety of their behaviour, often an older woman accompanying a young woman.
noun A protein that assists the non-covalent folding/unfolding and the assembly/disassembly of other macromolecular structures, but does not occur in these structures when the latter are performing their normal biological functions.
noun An employee sent by a British company to the European Union to work with a client there, to circumvent restrictions imposed after Brexit.