1. Something that is a means or method of accomplishing an objective.
2. Serving to promote one’s interest
3. Conducive to advantage or interest, as opposed to right.
Expedient sounds like experienced. Now, an experienced person knows how to promote his self interest and can be cunning along with being practical therefore this can easily be used to recall the meaning of the word expedient.
1. They found it expedient to negotiate with the terrorists.
2. Do the right thing, not the expedient thing.
3. In the circumstances it was expedient to express loyalty.