telescope

[icklebunnyuk]

what is a single lens telescope called

[Stano]

Reflectors only have one Lens, at the eye piece, two mirrors focus the light onto the eye piece.

[BadlyHungBoy]

A magnifying glass?

[Think Deep]

I think with a reflector, the mirrors would still be called lenses.
A refractor would have to have two lenses, or yes indeed, it would be a magnifying glass!