“To figure out a word's meaning, first find the shoiresh.” (Weiser)

“The shoiresh of the electrical problem was a mystery to even the chief electrician.” (Weiser)

“We traced the gemara to its shoiresh in Chumash.” (Weiser)

"what is ahavas yisroel? what is ahava? if we all come from the same shoiresh we dont differentiate." (source)