abbreviation for "Reverse Osmosis." Reverse osmosis is a process in which water is forced to travel through a semipermeable membrane against the concentration gradient by increasing the pressure on the feed side above the osmotic pressure of the solute with the highest osmotic pressure. It is often used in drinking water treatment.
People don't know that the reverse osmosis technology used to manufacture their bottled water does not do a good job removing neutral compounds like arsenious acid (arsenic), even though the companies bottline it would like you to think that it is ultra pure.
by Matt Charles February 15, 2005
Short for "Rot Off." A rot off is a member of the female persuasion who, as a result of engaging in sexual intercourse with multiple partners (males, females, animals etc.), is a host to a number of venereal diseases. The R.O. will then procede to spread the diseases, resulting in her partner's genitals rotting off.
R.O.'s include but are not limited to:
by R.L. Sparkes July 24, 2009