When is it stationery and when is it stationary?
Stationery functions as a noun and refers to office supplies like pens, pencils, paper, envelopes, etc.
Stationary functions as an adjective and describes things that are not moving and do not move or remain unchanged.
When to Use Stationery
Stationery is used as a noun and is defined as writing materials and office supplies; writing paper and envelopes.
Beautiful stationery is a gift in the form of a letter.
Studio Burke produces the finest quality, hand-engraved stationery.
The word stationery comes from the word stationer, an archaic word to refer to a bookseller or publisher.
One can remember stationery by the “e” that is the third to last letter. Stationery has envelopes, which begins with the letter "e". In addition to envelopes, the “e” matches many other supplies that stationery refers to, such as pens, pencils, letters, etc.
When to Use Stationary
Stationary is used as an adjective and is defined as not moving; not capable of being moved, fixed.
I bumped my automobile into a stationary vehicle.
This stationary piece of machinery is not going anywhere.
Stationary also has a more figurative meaning than the literal “not moving.” There is a figurative sense of the word that means unchanging in quantity or condition. For example, a sound that is steady, consistent, and unchanging might be described as being a stationary sound. Or if a city’s population has remained steady for a long period of time, you might say that it has a stationary population.
The word stationary comes from the Medieval Latin word stationarius, meaning belonging to a military station. Something (or someone) that was stationary became something that maintained its station.