Baffled

[bezzy]

1. Latin as before (2.2) 2. Soviet standard (7) ,

[cashier]

I think the russian standard is arshine or arsheen -you could google this word to see if it fits with your requirements

[elliemay1]

1. ut pro? But wrong number of letters.

[scorpiojo]

1 ibid

[frugalfred]

Ibid, abbrev. for ibidem, is one word.

[Baldric]

id em ?

[scorpiojo]

Is it baffler?

[Jackdaw33]

If ibid is the correct answer, and I have no reason to suspect otherwise, then it is a lousy clue. Ibid is short for ibidem which is written as one word, not two. If arsheen (or variant spelling) is correct then that is even worse, as an arshin was an old Russian length of distance which predated the revolution.

[elliemay1]

idem - definition of idem by The Free Dictionary
i·dem (ī′dĕm′) pron. Abbr. id. Something that has been mentioned previously; the same. [Latin, from id, it; see i-in Indo-European roots.] idem