About using words with extended ranges, there are English examples:-

"For a kickoff" for "for a start" used where football is not involved. (British usage)

"Under my thumb" and "wrapped around my little finger" started in falconry and referred to the route of a hawk's leash when it is sitting on my fist.

https://en.wikipedia.org/wiki/Falconry

Usage could easily extend from the start of an opera to the starts of other things.

----Original message----
From : sustel@trimboli.name
Date : 16/01/2017 - 15:16 (GMTST)
To : tlhingan-hol@lists.kli.org
Subject : Re: [tlhIngan Hol] <<poSayDon>> vImughlI'

On 1/16/2017 2:03 AM, Felix Malmenbeck wrote:

> wa'DIch would have been better. A bI'reS is the beginning of some artistic performance, not a job.

While I don't necessarily disagree with you, paq'batlh (paq'raD, Canto 14, Stanza 6) does give a precedent for using bI'reS as a timestamp.

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