The first line of the Wikipedia article on pensions is more accurate than wherever you’ve pulled that from:

> A pension (/ˈpɛnʃən/; from Latin pensiō 'payment') is a fund into which amounts are paid regularly during an individual's working career, and from which periodic payments are made to support the person's retirement from work.

A pension is a financial instrument. There’s no need to purchase an annuity, which means a pension organised correctly can be passed on to your children or spouse, and there’s no lottery or gamble angle.