Definition of tall oil in US English:

tall oil

noun

  • A resinous mixture of fatty acids, resin acids, and plant sterols recovered when resinous wood pulp is digested during paper-making, used in making lubricants, paints, and adhesives.

Origin

Early 20th century; earliest use found in Chemical Abstracts. From German Tallöl (1909; from Swedish tallolja from tall pine + olja oil), with substitution of oil for the second element.

Pronunciation

tall oil

/ˈtɑːl ɔɪl/