The word "in-spire" refers to the act of filling someone with enthusiasm, and its antonyms would be words that signify the opposite of that. Some possible antonyms might be words like discourage, dishearten, demotivate, depress, or dispirit. When someone is discouraged, their enthusiasm wanes, and they become less inspired. Feeling disheartened can make it difficult to feel motivated or inspired about anything, and becoming demotivated can mean giving up on things entirely. Depression and feelings of hopelessness can make it hard to find inspiration or motivation, and feeling dispirited suggests a loss of energy and enthusiasm. All of these adjectives are antonyms of the word "in-spire" and represent a lack of inspiration or enthusiasm.