John 8:4

The word "ἐπαυτοφώρῳ" (epautophōrō) occurs only once here in the NT. Generally when a special word shows up in the NT there is a really good reason for it. 

1. "ἐπί" (epi): A preposition meaning "upon" or "in."

2. "αὐτόφωρος" (autopōros): An adjective derived from "αὐτό" (auto), meaning "self," and "φωρός" (phōros), meaning "watching" or "observation." "ἐπαυτοφώρῳ" (epautophōrō) functions as an adverbial form of "αὐτόφωρος" (autopōros).

So, "ἐπαυτοφώρῳ" (epautophōrō) means "upon being self caught" or "self revealed."

(cf. LSJ αὐτοφώρατος)

The literal translations of "ἐπαυτοφώρῳ" (epautophōrō) are:

1. Upon self-observation.
2. Caught by oneself.
3. Self-caught.
4. Caught in the act by oneself.
5. Caught red-handed by oneself.