स्वस्वामिशक्त्योः स्वरूपोपलब्धिहेतुः संयोगः

sva svami saktyoh svarupopalabdhihetuh samyogah

Union is the powers of the owner and the owned causing the recognition of their own nature.

Yoga Sutras of Patanjali, 2.23

sva = being owned
svami = owner
saktyoh = of the powers
svarupa = own nature
upalabdhi = recognition
hetuh = cause
samyogah = union