These are two different words that may be a little similar. But they usually cannot be used interchangeably. Expedient means something that is convenient or practical, easy and quick. But often also means something that isn’t the best possible option, just the easiest. Ex. It’s expedient and easy to cook meat quickly. However, it may be raw and undercooked, so maybe the expedient option may not be best. Appropriate means something that is suitable for the situation. Ex. It’s appropriate to bring a pencil to school. It’s inappropriate to bring a jump rope to school. I hope this helps!

So expedient does mean “practical” or “appropriate”. However, what is expedient can also be “improper” or “immoral”. So it was more of a negative feelings behind it. Example sentence would be “it was expedient to fire all of the employees when the market crashed.”