Ad interim
The Latin phrase ad interim (abbr. ad int., literally "in the time between") means "in the meantime" or "temporarily".
A diplomatic officer who acts in place of an ambassador is called chargé d'affaires ad interim.
Examples
Examples from classic literature:
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No; but she has become queen of Paris, ad interim. and since she could not venture at once to establish herself in the Palais Royal or the Tuileries, she is installed at the Hôtel de Ville, where she is on the point of giving an heir or an heiress to that dear duke.
- — chapter 77 of the English translation of Twenty Years After by Alexandre Dumas, père[1]
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Ad interim, if I may be pardoned that expression, I shall give you this betel-box, which is highly valuable article and cost me two rupees only four years ago.
- — Kim by Rudyard Kipling
The abbreviation a.i. is used in job titles. E.g. Director of Operations, a.i.