To Rub

Lingual

1. (transitive) To move (one object) while maintaining contact with another object over some area, with pressure and friction.
2. (transitive) To rub something against (a second thing).
3. (intransitive) To be rubbed against something.
4. (transitive) To spread a substance thinly over; to smear.
5. (dated) To move or pass with difficulty.
6. To scour; to burnish; to polish; to brighten; to cleanse; often with up or over.
7. To hinder; to cross; to thwart.
8. (transitive, bowls) To touch the jack with the bowl.

Linguistics

Probable connection to the verb رَبَّ

Unlike the uncanny alignment of friction and faraka, the English verb rub and the Arabic رَبَّ (rabba) represent a classic "false friend"—a pure phonetic coincidence. They share a nearly identical sound profile, but their semantic trajectories and historical origins belong to entirely different conceptual universes.

The Expressive Origin of "Rub"

The English verb originates from the early 14th-century Middle English rubben. Unlike friction, which traces clearly back to Latin and Proto-Indo-European, rub lacks a deep, structured etymological lineage.

• Sound Symbolism: Historical linguists generally classify it as an expressive or imitative word that arose organically within Germanic languages (matching the Low German rubben or East Frisian rubben). The phonetics—a vocalic trill or approximant /r/ followed by the heavy, closed bilabial stop /b/—acoustically mimics a blunt, repetitive, back-and-forth physical action. It shares this imitative, action-oriented sound profile with similar English words like scrub or stub.

The Semitic Root ر-ب-ب (r-b-b)

In Arabic, the geminate (doubled) root ر-ب-ب (r-b-b) has no connection to physical friction, abrasion, or scraping. (The physical act of rubbing in Arabic relies on roots like د-ل-ك d-l-k or ف-ر-ك f-r-k). Instead, the r-b-b root governs a semantic field of mastery, nurturing, sustaining, and bringing something to a state of completion or density.

• Mastery and Nurturing: The most prominent derivative is Rabb (رَبّ), meaning Lord, Master, or Sustainer. This structural concept of elevating or rearing gives us the verb رَبَّى (rabba), meaning to raise, educate, or nurture, which is the foundation of tarbiyah (تَرْبِيَة) for upbringing.
• Physical Thickening: In a more material sense, the root describes collecting and concentrating a substance until it becomes dense. For example, rubb (رُبّ) refers to a thick, boiled-down fruit syrup or molasses (like carob or date syrup).

The Hidden Crossover

While the English action of rubbing shares no ancestry with رَبَّ, the Arabic root did quietly enter the English lexicon. Through medieval Mediterranean trade and pharmacology, the Arabic rubb (thickened fruit syrup) entered Middle French as robbe, and subsequently English as rob—a historical culinary and apothecary term for a thickened fruit juice used as a medicinal base.