赞许 is a formal noun meaning 'approval' or 'commendation', often expressing positive recognition of someone's behavior, achievement, or attitude. The first character 赞 (zàn) means 'to praise' or 'to laud', while 许 (xǔ) here carries the sense of 'to approve' or 'to consent' — together, they form a compound emphasizing respectful, often quiet or dignified affirmation rather than enthusiastic cheering.

This word is commonly used in written Chinese and formal speech — for example, in education, workplace feedback, or news reports — and frequently appears after verbs like 表示 (to express), 得到 (to receive), or 面露 (to show on one’s face). It conveys sincerity and seriousness, making it unsuitable for casual praise among friends. While it can function as a verb in rare literary contexts, its overwhelmingly dominant use is as an uncountable noun.