The noun sentiment can be countable or uncountable. In more general, commonly used, contexts, the plural form will also be sentiment. However, in more specific contexts, the plural form can also be sentiments e.g. in reference to various types of sentiments or a collection of sentiments.

Is sentiment a countable noun?

1[countable, uncountable] (formal) a feeling or an opinion, especially one based on emotions the spread of nationalist sentiments This is a sentiment I wholeheartedly agree with.

How do you use the word sentiments?

Word forms: sentiments

Public sentiment rapidly turned anti-American. He's found growing sentiment for military action. A sentiment is an idea or feeling that someone expresses in words. I agree with those sentiments.