The word "Siman" in the names of some tanks

I was curious, why do tanks say “Siman” instead of “Mk” (Mark)? I have kind of been doubting it’s accuracy since it was added; as, around the time it was introduced, a friend of a friend who spoke hebrew said that they used “Siman” in it’s “translate-equivalent” but not what it actually means.

A cursory google search says that “Siman” translates to Mark, however it means “Mark” as in an omen, or sign, and not what would be the accurate “translation” for Mk, being “version.” In essence, “Siman” means “Mark” in a religious sense and not a designation sense.

Siman - Mark, Sign, Omen

A siman is a mark, sign or omen. The root is the verb soom, which means to put or place and so also to mark or distinguish.

Siman - Translateable?

“Siman” is one of the many words Hebrew adapted from Greek (“semeion”) and it has many different meanings: In the Talmud it is often used as sign or proof (Baba Metziah, Yevamot 79a) as well as a sign of an animal being kosher (Chulin 27b) etc… It can also be a signal: “Tesamen li” (give me a signal)…

Additionally, at least from my knowledge, it wouldn’t make sense to use “Siman” instead of “Mk,” since the Israeli designers took inspiration from the British (and had their help, iirc), who used “mark” as “version,” and this (Mk) has been transliterated/directly absorbed into other languages before.
Was the word “Siman” used to describe versions of tanks, or versions of anything? Was there a different word? Or would it have just been “Mk” for describing versions?

What tanks say siman instead of mk?

Merkavas
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