Final answer:
The word 'ennui' means boredom, representing a feeling of listlessness and dissatisfaction due to a lack of excitement or interest.
Step-by-step explanation:
The word 'ennui' means boredom or a feeling of listlessness and dissatisfaction arising from a lack of occupation or excitement. It is a loanword from French, where it denotes the same sense of tedium. The correct answer to the question of what 'ennui' means is option 3) boredom. Unlike excitement, interest, or happiness, ennui describes a state that is often linked with monotony or the doldrums of life, where one might feel uninspired, disinterested, or filled with a sense of weariness.