Oleum

Oleum or the plural olea is used in different meanings:

Oleum (Latin for oil ) as in petroleum
in pharmacy and medicine for oil (abbr .: Ol. from Latin oleum ), see oils
in chemistry for fuming sulfuric acid (concentrated sulfuric acid H ₂ SO ₄ with e.g. 24, 34 or 65% by weight of dissolved sulfur trioxide SO ₃ )
in chemistry partly for disulfuric acid
in botany for the genus of olive trees ( Olea )
In the petrochemical industry, Olea Mineralölwerke AG was the founding name of what later became Deutsche Gasolin AG, see Gasolin (petrol station chain)

Olea is called