Marjoram, Origanum marjorana, is related to oregano. Marjoram has grey-green oval leaves.
The marjoram plant has a mildly savoury, grassy aroma that is very similar to thyme, but with more camphorous and sweet spicy notes to it. Unlike some herbs, both marjoram and oregano have a better flavour when dried as this seems to concentrate in the exotic camphor flavours, creating a more intense flavour burst.
Marjoram has a more delicate (less robust) flavour than oregano, but can likewise be used in Italian cooking, e.g. on pizzas. Marjoram works well with chicken and fish as well as egg dishes and when cooking mushrooms. It also is a good flavour in stuffings, where it is less overpowering than some other herbs, and can be used to flavour ratatouille. Marjoram works well with oregano, rosemary and thyme to develop herbal flavour mixes.