What is the Greek word for collaborate?

There isn't one single perfect Greek word that translates directly to "collaborate" in the modern sense. The best translation depends on the nuance you want to convey. However, here are some options, each with slightly different connotations:

* συνεργάζομαι (synergázome): This is probably the closest single word. It means "to work together," "to cooperate," and implies a joint effort towards a common goal. It's a very common and widely understood term.

* συμβάλλω (sumbállō): This means "to contribute," "to participate," or "to cooperate." It emphasizes the contribution of each individual to the larger project.

* συνεργασία (synergasía): This is the noun form of συνεργάζομαι, meaning "collaboration" or "cooperation."

The best choice depends on the context. For most situations, συνεργάζομαι (synergázome) is the most accurate and versatile option.