This surname originated from the south-western Middle English word for a stream or river - ya, yeo, yo. The Old English word is 'ea'. The word gave rise to a number of placenames in both Devon and Somerset, leading to the use of the surname Yeo as a description of someone who lived in those places. 

It was also used to describe someone who lived near to a river or stream. An early example of the surname is Nicholao de Ya, named in a c.1228 Deed from Totnes Priory, Devon. This name translates to Nicholao of Ya, and may be an example of the name before it was used as a hereditary one.

Variants of this surname include Yea, Yow, Yoe, Youe. In 1881, Devon was the county with the highest population of people named Yeo.