Bradbury has purposely separated the word into two parts. Dis- is a prefix meaning "not" and ease is a word meaning "comfort" (Webster's New World Dictionary). He and Clarisse had been meeting every day on his way to work for a week. When she was suddenly no longer there, he didn't know what was wrong but he was "not comfortable" with the situation. "Something was the matter, his routine had been disturbed." pg. 32 . He felt a loss. He found himself looking for her on the street, in the trees, and on the lawn. He almost retraced his steps on the way to work so that he could meet her again. Later in the book, (pg 78) Montag thinks "I'm numb, he thought. When did the numbness really begin in my face? In my body. The night I kicked the pill bottle in the dark, like kicking a buried mine." That was the night he met Clarisse. When he is on the run, Faber tells him that he did what he had to do and that it had been coming on for a long time. Montag agrees stating that 'I went around doing one thing and feeling another. God, it was all there. It's a wonder it didn't show on me, like fat" (pg 131). But it did show on him. That is how Beatty noticed it, and the Hound sniffed it out.