勤奋 is an adjective meaning 'diligent' or 'industrious', describing someone who works hard, shows persistent effort, and is committed to learning or achieving goals. The character 勤 means 'to be diligent, attentive, or conscientious', often implying regular, careful action. The character 奋 means 'to exert oneself, strive, or make a vigorous effort', carrying connotations of energy and determination. Together, 勤奋 emphasizes both consistent, steady effort (勤) and spirited, purposeful striving (奋), making it stronger than either character alone.

This word is commonly used in academic, professional, and personal development contexts — for example, praising students, describing work ethic, or encouraging self-improvement. It carries a positive, respectful tone and frequently appears in formal speech, writing, and motivational phrases. While it can modify nouns directly (e.g., 勤奋的学生), it’s more often used predicatively (e.g., 他很勤奋) or as a subject complement after 是.