Hayom Yom 9 Teves - The wording in the prayer of Aleinu

נְהִיגִין בְּנוּסַח עָלֵינוּ לוֹמַר: שֶׁהֵם מִשְׁתַּחֲוִים לָהֶבֶל וְלָרִיקIn the prayer beginning Aleinu, the wording that we customarily follow is, “…for they bow down to vanity and nothingness.” וְגַם בִּתְּפִלַּת מוּסָף דְרֹאשׁ הַשָּׁנָה אוֹמְרִים כֵּןThis version is also used in the Mussaf prayers of Rosh HaShanah. וּמְדַיְּיקִים שֶׁלֹּא לוֹמַר וּמִתְפַּלְלִים כוWe make a point of not saying, “and they pray [to a god who]….”הָרְקִיקָה הִיא אַחַר הָאֲמִירָהIt is customary to spit after reciting the above phrase. טַעַם הָרְקִיקָה, כִּי מִדִּבּוּר מִתְהַוֶּה רוֹק, וְאֵין רוֹצִים לֵיהָנוֹת מֵרוֹק זֶהThe reason is that speaking generates saliva, and we do not wish to benefit from the saliva generated by uttering such words.Text and Translation courtesy of Sichos in English