Ionesco's Rhinoceros fits most definitions of the theatre of the absurd because:
1. It is a play about being and existence. Berenger is the "last man" in that he is struggling against a chaotic universe which ultimately becomes absurd and nonsensical.
2. It is concerned with language, communication, and understanding. There is a humourous discussion of the definition of "cat" and "catness" by a logician who is not very logistical. Many characters cannot communicate and understand eachother throughout the play and it only deteriorates as most of the characters turn into or join the rhinos.
3. It is humourous, but at the same time it's tragic and carries with it serious social undertones. Ionesco's play is a comment on facism and how some people blindly subscribe to ideas and messages because "everyone else does."
4. It has absurd elements. A herd of rhinos running amuck in a small, provincial French town?!?!?! The inhabitants are uncaring save the difference between an "Asiatic" and "African" rhino?