Sentence:  When the other animals came back to luncheon, very boisterous and breezy after a morning on the river, the Mole, whose conscience had been pricking him, looked doubtfully at Toad, expecting to find him sulky or depressed. Instead, he was so <WSD>uppish</WSD> and inflated that the Mole began to suspect something; while the Rat and the Badger exchanged significant glances. 
Meaning of the word marked with <WSD> tags:  proud; arrogant; assuming