Vis a vis "rub of the green"
I have heard it argued that this expression has no nautical origin per se, but in fact comes from the sport of lawn bowls. Lawn bowls is, obviously, played on a grass surface (this is known as a "bowling green", probably from the old english
village-green which is a communal grassy area in the centre of the village, used for festivals, fetes, dances, etc.)
The green would, as a rule
, not be absolutely perfectly flat...each green would have its own little idiosyncracies - slope to one end, or slight hollows or mounds, even the way the grass had been cut - these peculiarities were known as "the rub
of the green". Obviously, such peculiarities could either hinder or help the bowler, depending on the circumstances - sometimes one might actually benefit, sometimes not.So, when playing, is some vagary of the slope or nap of the playing surface actually helped a bowler, they would be said to "have the rub of the green".