Squirrel profanity is extremely funny. It begins with a volley of rapid and explosive "chuck!" sounds. This is followed by a long period of the squirrel making other sounds which are harder to render into any printed word. Let's call them "skraaks" for lack of a better word. He also twitches his tail and various parts of his body as he skraaks, jumps around, and does everything possible to show just how very upset he is with you. An infuriated squirrel will go on issuing skraaks for quite a long time, and if you imitate him, make aggressive gestures, or in any way respond in kind he will go on much longer yet. It's great entertainment on a slow day.