אֻכְלוּסִיָּה
The word used in Modern-Hebrew to refer to a specifc population is the same as that used in Mishnaic times: אֻכְלוּסִיָּה (ookh-loo-see-YAH).
For example:
גֹּדֶל אֻכְלוּסִיַּת יְרוּשָׁלַיִם מִתְקָרֶבֶת לִשְׁמוֹנֶה מְאוֹת אֶלֶף תּוֹשָׁבִים – The size of the population of Jerusalem is approaching eight hundred thousand residents (GOH-del ookh-loo-see-YAHT yeh-roo-shah-LAH-yeem meet-kah-REH-vet leesh-moh-NEH meh-OHT EH-lef toh-shah-VEEM).
To refer to population in general, you’d use the word אֻכְלוּסִין (ookh-loo-SEEN).
For example, הַרְבֶּה אֲנָשִׁים מֻדְאָגִים מֵהִתְפּוֹצְצוּת אוכלוסין -Many people are concerned about population explosion (overpopulation) (hahr-BEH ah-nah-SHEEM mood-ah-GHEEM meh-heet-poh-tseh-TSOOT ookh-loo-SEEN).
This now-Hebrew word is actually borrowed from the Ancient Greek όχλος (OHKH-lohs), meaning masses.
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