* κτίσμα (ktisma): This word literally means "creation" or "thing created." It's a broad term that can encompass any living being, but it emphasizes the act of creation. It's less frequently used for everyday animals than other options.
* ζῷον (zōion): This is a common and versatile term referring to an "animal" or "living being." It's a broad category and can include humans, but typically implies a non-human animal.
* πλάσμα (plasma): Similar to *ktisma*, this word means "thing formed" or "creature." It often suggests something formed from a less defined substance. It can be used for a living being, but carries an implication of something perhaps less substantial or more vaguely defined.
* θῆρ (thēr): This word means "wild beast" or "beast of prey." It specifically refers to dangerous or savage animals.
* ἄνθρωπος (anthrōpos): This is the word for "human being" or "man." While technically a creature, it's very specific and not a general term.
* ὄν (on): This word means "being" in a philosophical sense. It refers to existence itself and could encompass any creature or thing that exists. However, it's not used as a colloquialism for "creature."
The best choice depends entirely on the context. If you can provide a sentence or context, I can help you choose the most appropriate Greek word.