Following on from my previous post - I noticed a few things about this word.
For example in Acts 22:2 the crowd became "even more quiet" . Here the word "silent" in English is not appropriate translation of this word - because silence in English doesn't have degrees. It's hard to be silent, and then be even more silent. You're either silent or not. So this word ηεσυχια has degrees, which are not so appropriate in English.
In the previous post, I gave the NRSV examples. The ESV more consistently uses the word "quietly" for this word, but even the ESV was not able to coherently translate the Luke 23:56 example with "quiet". The ESV also has "On the Sabbath they rested according to the commandment." This word has a range of meaning which doesn't easily fit with any English word. It seems to imply orderly behaviour which is submissive to God. I don't know of any English word which includes all these meanings - do you?