A mixture of herbs and spices that was used for flavor in early beer and mead brewing. Gruits were replaced by hops, because the recipes for gruits were closely held secrets, whereas it's hard to keep plants a secret.
Gruit (or sometimes grut) is an old fashioned herb mixture used for bittering and flavouring beer, before the extensive use of hops. Gruit or gruit ale may also refer to the beverage produced using gruit.