What is the greek word that means perpetual and ongoing?

There isn't one single perfect Greek word that captures the exact nuance of "perpetual and ongoing" in all contexts. The best choice depends on the specific application. However, some options that come close include:

* ἀϊδιος (aidios): This word means "eternal," "everlasting," or "perpetual." It emphasizes the timeless and unending nature of something. This is likely the closest single word.

* ἀδιάλειπτος (adialeiptos): This means "uninterrupted," "unceasing," or "continuous." It highlights the lack of breaks or pauses in the process.

* αἰώνιος (aionios): Similar to *aidios*, this word refers to something that belongs to or lasts for an *aeon* (a long period of time, often associated with eternity).

The best choice will depend on the context. If you are describing something that never ends, *aidios* or *aionios* are good choices. If you are emphasizing the continuous nature of something without necessarily implying eternity, *adialeiptos* might be more suitable.