Context. This is a genuine image of a cross section of grass leaf under a microscope. No part of the leaf is "smiling" in any literal sense, of course, but the round features known as "vascular ...

A monocot is a plant that, when germinating, produces one seed leaf or cotyledon. 'Mono' means one and 'cot' refers to cotyledon. Any plant that has a single leaf at germination is called a monocot.