put in the place of another; switch seemingly equivalent items;
"the con artist replaced the original with a fake Rembrandt"
"substitute regular milk with fat-free milk"
"synonyms can be interchanged without a changing the context's meaning"
give to, and receive from, one another;
"Would you change places with me?"
"We have been exchanging letters for a year"
cause to change places;
"interchange this screw for one of a smaller size"
reverse (a direction, attitude, or course of action)