añejo
From The Oxford Companion to Spirits & Cocktails
, the Spanish word for “aged” or “mature,” is used as a descriptor for several different types of aged spirits. By law, tequila and mezcal must be aged in wooden containers for a minimum of one year to be called añejo. There are also añejo rums; these spirits are generally aged for a significant amount of time, but there is no legal regulation of the use of the term with rum.
This definition is from The Oxford Companion to Spirits & Cocktails, edited by David Wondrich (Editor-in-Chief) and Noah Rothbaum (Associate Editor).