Deferring means applying for a course then taking a year out before going to university. Usually, you can only defer your entry by one year.
Some universities will allow you to defer, typically for a year. Some universities and colleges do not allow deferred entry for some subjects, and some will allow you to apply with deferred entry, whilst other will allow you to defer after having been admitted. University research is required.
​Please make sure you look into the conditions of the deferment. Also please be aware that some universities will not allow you to take any university lessons at another institute for a year; getting credits at any university might mean you lose your deferment option.
Source: https://www.ucas.com/undergraduate/applying-university/when-apply/deferred-entry (accessed on 10th February, 2021)
For more information about deferred entry to the UK (via UCAS), please click on the button below: