The word was "another" and the passage was John 14:16:
"I will ask the Father, and He will give you another Helper, that He may be with you forever; that is the Spirit of truth, whom the world cannot receive, because it does not see Him or know Him, but you know Him because He abides with you and will be in you. - John 14:16-17
The Greek word behind "another" here is allos which "expresses a numerical difference and denotes 'another of the same sort;'." The Spirit and Yeshua are the same.
There is another Greek word that is related to allos: heteros. Heteros means "another of a different sort".
In Romans 7:23 Paul observes "I see a another law," (heteros,): a law different from that of the spirit of life (not allos, "a law of the same sort").
M-W provides the following etymology for cognate:
The story of "cognate" is all relative: that is, it's all about relatives. Cognate words share an ancestor, like "allude" and "prelude" (which both trace to the Latin root "ludere") and the English "brother" and the German "Bruder" (which are both related to the Greek "phrater"). Cognate languages, like French, Spanish, and Italian, descend from the same ancestral language. People related through a common ancestor are cognate, and groups of people, such as tribes, can be cognate to one another. "Cognate" also describes things related in a more figurative way, as in "cognate developments," "cognate disciplines," or "cognate problems." "Cognate" itself comes from the Latin "cognatus" which traces to Latin "nasci" meaning "to be born." Some words cognate to "cognate" include "innate," "nascent," "native," and "Renaissance."
The Spirit and Yeshua are the same nature (cognates). Yeshua stated "I and the Father are one." (John 10:30)