This is the 4366th most frequent Japanese word.
反日
"Anti-Japanese" or "opposed to Japan or Japanese interests."
The term '反日' is used as an adjective to describe '感情' (sentiments) indicating 'anti-Japanese' sentiment.
反日感情が高まっている地域があります。
There are regions where anti-Japanese sentiments are increasing.
Here, '反日' is formed as a part of the adjective '反日的', describing something as related to being 'anti-Japanese'.
彼の発言は反日的だと批判されました。
His statement was criticized as being anti-Japanese.
In this example, '反日' is used as an adjective modifying 'デモ' (demonstration), implying that the demonstration was held with anti-Japanese objectives.