Vaisesika Sūtra 6.2.16

तत् संयोगो विभागः ॥१६॥

tat saṁyogo vibhāgaḥ ॥16॥

[तत् (tat) - that; संयोगः (saṁyogaḥ) - union; विभागः (vibhāgaḥ) - separation;]

That is union (saṁyogaḥ) and separation (vibhāgaḥ).