osculation

nouns

(mathematics) a contact of two curves (or two surfaces) at which they have a common tangent
is derived from
domain category
a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement
is a type of (narrower)
the state or condition of touching or of being in immediate proximity
"litmus paper turns red on contact with an acid"
the act of caressing with the lips (or an instance thereof)
is derived from