Choke up is a term used to describe a situation where something becomes blocked or obstructed. CLOG and JAM are two words that can be used to describe this situation. CLOG is a four letter word that means to block or obstruct, usually with a solid material such as mud or debris. JAM is a three letter word that means to become stuck or blocked, usually due to an excess of something such as traffic or people. Both words can be used to describe the situation of choke up.