sap

English "sap" comes from Old English sæp, meaning juice or sap, from Proto-West Germanic *sap, itself from a Proto-Indo-European root meaning "to taste."

The word has stayed remarkably close to its roots — from a root meaning "to taste" to Old English sæp for tree juice, straight into modern English sap.

It shares its root with the word "sage" (as in the wise sense), and is cognate with Dutch sap, German Saft, and Icelandic safi — all words for juice or sap in their own languages.