Sat is the past tense of the verb sit, meaning you took a seat or rested in a seated position. If you sat down at your desk this morning, you lowered yourself into your chair. If you sat through a long assembly yesterday, you remained seated the whole time.

The word describes the completed action of sitting. “I sat on the bench” tells us it already happened, while “I sit on the bench” means it's happening now. You might say you sat still during a serious conversation, sat up straighter when the principal walked in, or sat cross-legged during story time.

People also use sat in interesting phrases. When someone sat on their hands, they chose not to take action. If a project sat on a shelf for months, it remained there unused and forgotten. And if you sat tight during a storm, you stayed put and waited patiently for it to pass.

Notice that sat is irregular: we don't say “sitted” the way we'd say “walked” or “talked.” English has many irregular past tense verbs like this, where the word changes form rather than just adding “-ed.”