Webster's Revised Unabridged Dictionary · 1913

Osculate

Osculate , transitive verb

[Latin osculatus, past participle of osculari to kiss, from osculum a little mouth, a kiss, dim. of os mouth. See Oral, and compare Oscillate.]

1.
To kiss.
2.
(Geometry) To touch closely, so as to have a common curvature at the point of contact. See Osculation, 2.

Osculate , intransitive verb

1.
To kiss one another; to kiss.
2.
(Geometry) To touch closely. See Osculation, 2.
3.
(Biology) To have characters in common with two genera or families, so as to form a connecting link between them; to interosculate. See Osculant.