[cgio]

The Turkish password word may be the same used for signature? I suspect so, because in Greek we have the Greek word for signature but also a Turkish loan word τζίφρα (djifra).

[esafak]

imza is signature while şifre is password. I imagine the conflation occurred because signatures are used like passwords for authentication...

[NextHendrix]

Likewise, the monogram of the sitting english monarch (as seen on postboxes and so forth) is the "Royal Cypher".

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

[pinkmuffinere]

Hmm i don’t think that one is related in Turkish — i only know of “imza” as signature, but there could also be other variants.