This is the 14363rd most frequent Russian word.
отметят
"Отметят" means "will mark" or "will celebrate."
The word "отметят" indicates the action of celebrating a specific event by people.
Люди отметят праздник Новый год на площади.
People will celebrate the New Year's holiday in the square.
Here, "отметят" refers to the act of marking or indicating completion.
Ученики отметят выполнение своих заданий галочками.
Students will mark their task completion with checkmarks.
In this sentence, "отметят" is used to denote the act of pointing out or emphasizing an aspect.