Stop up and Sit-up

Stop up verb - To prevent passage through by filling with something.

Sit-up and stop up are semantically related. In some cases you can replace phrase "Sit-up" with "Stop up", this terms are similar.

Sit-up noun - A stomach exercise in which a person sits up from a supine position without using the arms for leverage.

Stop up and sit-up are semantically related. You can use "Stop up" instead a verb phrase "Sit-up".