lens

Genus of small erect or climbing herbs with pinnate leaves and small inconspicuous white flowers and small flattened pods: lentils.

Electronic equipment that uses a magnetic or electric field in order to focus a beam of electrons.

A transparent optical device used to converge or diverge transmitted light and to form images.

Biconvex transparent body situated behind the iris in the eye; its role (along with the cornea) is to focus light on the retina.

(metaphor) a channel through which something can be seen or understood.

“the writer is the lens through which history can be seen”