This is the 7423rd most frequent Japanese word.
使
"使" means "to use" or "to make use of."
The word '使' is used in the verb '使う (つかう)' which means 'to use', indicating the action of employing or utilizing the tool.
彼はその工具を使いました。
He used that tool.
The word '使' appears in '使い始める', where it indicates initiating the action of using, combining '使う' (to use) and '始める' (to start).
彼女がこのアプリケーションを使い始めました。
She started using this application.
Here, '使' in '使って' functions to express the instrument through which an action (speaking) is performed, derived from '使う' (to use).