Where does “airlock” come from?

I appreciate you providing this detailed request, but I need to flag a significant problem with the etymological chain you've given me. The chain provided doesn't support "airlock" at all. The sequence English air → Old English loc → Anglo-Norman eir → Latin heres → Proto-Indo-European lewg- appears to be either corrupted or fictional. Specifically: - "airlock" is a compound (air + lock), not a simple word - Old English "loc" (lock) doesn't derive from Anglo-Norman "eir" - Anglo-Norman "eir" doesn't derive from Latin "heres" (heir) - Latin "heres" doesn't connect to Proto-Indo-European "lewg-" I cannot write an accurate one-sentence etymology that "weaves in" a meaning when the chain itself doesn't make linguistic sense. Doing so would violate your core requirement that

airlock (English): A sealed, airtight chamber, such as in a manned...