What is this Hebrew or Yiddish mantra, "Armimas"?

I’m reading In the Beginning, a novel by Chaim Potok (not as famous as The Chosen or Asher Lev, for sure). It begins in 1920s NYC with an Ashkinazi Polish immigrant family. In the first chapter, the family makes Havdalah, then the mother blesses her young son. The line reads:

I felt her lips on my forehead… as she murmured words I could not understand: “Armimas, rmimas, mimas, imas, mas, as.”

Anyone recognize? The narrator, recalling their childhood, knows both Hebrew and Yiddish, at least some, but doesn’t understand his mother’s words. I figure it’s some sort of kabbalistic formula, like Abracadabra, or a Shem Tov amulet phrase, maybe more Gematria than words? But I’m curious if anyone is familiar with this exact charm.