Lacking anything that could make someone smile or laugh.
用法筆記
More formal than 'funny'. Commonly used before nouns (a humorous remark) or after linking verbs (the story was humorous). In everyday spoken English, 'funny' is much more frequent.
常見錯誤
What a humorous joke!' (too formal for casual situations).
What a funny joke!
'humorous' sounds written or formal; 'funny' is the natural choice in everyday speech.