RuneScape Classic Wiki
RuneScape Classic Wiki
The main RuneScape Wiki has an article on: Lime
The Old School RuneScape Wiki also has an article on Lime.

A Lime is a green fruit used in Gnome Cuisine, most often used in Gnome cooking. When eaten directly it will restore 2 Hits.

It can be diced with a knife into Lime chunks, or sliced with a knife into Lime slices, which both heal 2 Hits points each. Can be bought from Heckel Funch's groceries for 2 coins in the Grand Tree.