What is greek for large stone?

There isn't one single perfect Greek word for "large stone," as the best choice depends on the context. However, here are some options with slightly different nuances:

* λίθος μέγας (lithos megas): This is the most straightforward translation, literally meaning "stone big." It's grammatically correct and easily understood.

* πέτρα μεγάλη (petra megalo): Similar to the above, but using "πέτρα" (petra), which generally refers to a rock or boulder, often implying a larger size than "λίθος" (lithos).

* βράχος μεγάλος (brachos megalo): This uses "βράχος" (brachos), which signifies a crag, cliff, or large, rugged rock. This implies a significantly larger and more imposing stone than the previous options.

The best choice depends on the specific size and type of stone you're describing. If you can provide more context, I might be able to suggest a more precise word.