Osmose

Osmose. If two liquids be separated from each other only by a skin or parchment, each will percolate through the membrane and diffuse into the other; the process is known as osmose, and is constantly illustrated in the animal and vegetable world.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Osmanlis * Osnabrück
[wait for the fun]
Orsini, Felice
Orsova
Orviëto
Oscans
Oscar I.
Oscott
O'Shaughnessy, Arthur
Osiander, Andreas
Osiris
Osmanlis
Osmose
Osnabrück
Ossa
Ossian
Ostade, Adrian
Ostend
Ostia
Ostracism
Ostrogoths
Oswald, St.
Oswego