bʰruHg-
“to enjoy, to use”use, enjoy, fruit
Root for using/enjoying, yielding Latin frui/fructus, English fruit, brook (to bear).
Discussion
The PIE root *bʰruHg- (to enjoy, to use, to have the benefit of) produced the Latin vocabulary of enjoyment and the concept of fruit — that which is enjoyed, the product whose consumption is the purpose of cultivation.
Latin fruī (to enjoy, to have the use of — past participle frūctus) continues the root and gave English: fruit (frūctus, "that which is enjoyed" — the product of a plant, then any beneficial result), fruition (the state of enjoying, of bearing fruit), fructify (to bear fruit), and usufruct (the legal right to enjoy the fruits of another's property — ūsus + frūctus). The word frugal (from frūgī, "useful, economical" — one who uses things properly, who enjoys without waste) connects to the same root: frugality is the art of proper enjoyment.
The semantic chain use → enjoy → fruit → result encodes an agricultural philosophy: the fruit is the purpose of the plant, enjoyment is the purpose of work, and proper use is the measure of good management. The PIE speakers who named the act of enjoying generated the vocabulary of both orchards and economics.
Notes
Pokorny 173. English fruit, frugal, brook (to tolerate).