Sorrow, grief; mental suffering or anguish.
Etymology: Around 1300, from Latin dolor, pain, or dolere, to suffer.
'Dolorous' is an adjective meaning painful, sorrowful, or wretched.
A dolorimeter is an instrument used to measure pain.
'Dol' is an obsolete unit of intensity of pain, used in the Hardy-Wolff-Goodell pain scale. The scale was based on the pain sensations felt by people when their skin was heated. But the results could not be reproduced, and both pain scale and unit of measure were eventually replaced.