(idiomatic) According to one's understanding.

Alternative spelling of plus one

According to one's subjectively formed thoughts, not necessarily having any formal basis in fact.

(informal, idiomatic) Someone who is easily fooled, victimized, or ridiculed. / (informal, idiomatic) Someone who is eccentric, nonconformist, or otherwise peculiar.

(informal) in one attempt

plural of one-shot

Third-person singular simple present indicative form of one up

Something extremely rare or unlikely.

Composed of a single integral unit or so appearing.

(mathematics, in two dimensions) Describing a simple spiral that starts at a point at the origin and does not divide the plane / (mathematics, in three dimensions) Describing a section of a simple helix