Rub, n.
 1. The act of rubbing; friction.
 2. That which rubs; that which tends to hinder or obstruct motion or progress; hindrance; obstruction, an impediment; especially, a difficulty or obstruction hard to overcome; a pinch.
    Every rub is smoothed on our way.   --Shak.
    To sleep, perchance to dream; ay, there's the rub.   --Shak.
    Upon this rub, the English ambassadors thought fit to demur.   --Hayward.
    One knows not, certainly, what other rubs might have been ordained for us by a wise Providence.   --W. Besant.
 3. Inequality of surface, as of the ground in the game of bowls; unevenness.
 4. Something grating to the feelings; sarcasm; joke; as, a hard rub.
 5. Imperfection; failing; fault. [Obs.]
 6. A chance. [Obs.]
    Flight shall leave no Greek a rub.   --Chapman.
 7. A stone, commonly flat, used to sharpen cutting tools; a whetstone; -- called also rubstone.
 Rub iron, an iron guard on a wagon body, against which a wheel rubs when cramped too much.
 Rub of the green Golf, anything happening to a ball in motion, such as its being deflected or stopped by any agency outside the match, or by the fore caddie.
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