'teary' originates from the English word 'tear,' specifically the word 'tearful,' where 'tear' meant 'a drop of clear salty liquid secreted by glands in your eyes.'

'tearful' transformed into the adjective 'teary' in modern English usage.

Initially, it meant 'full of tears,' but over time it evolved into its current meaning of 'having tears in the eyes or appearing as if about to cry.'