'two-bearing' originates from English, specifically a compound of the numeral 'two' and the noun 'bearing', where 'two' comes from Old English 'twā' meaning '2' and 'bearing' comes from Old English 'beran' (via Middle English) where the sense developed to 'direction' or 'the act of bearing (carrying/orienting)'.

'bearing' changed from Old English 'beran' (verb) and its descendant noun forms in Middle English ('bearing') and eventually became the modern English noun 'bearing' meaning 'direction, orientation'; 'two' comes from Old English 'twā' and evolved into the modern numeral 'two'. The compound 'two-bearing' is a modern formation combining these elements to describe a measurement or fix derived from two bearings.

Initially, 'bearing' primarily related to 'carrying' or 'bearing' in the sense of 'to carry', but its sense shifted to include 'direction' or 'orientation'; combined with 'two' it came to mean 'having or derived from two directions/bearings.'