A word meaning “steadfast, trusty man, faithful vassal” developed from the primitive form ᴹ✶bóron- (Ety/BOR). Because the initial syllable was stressed in the primitive form, the initial [bor-] did not reduce to [br-] as it did when the primitive vowel was unstressed. The glosses seem to indicate that it could be used as an adjective “steadfast” or a noun “trusty man, faithful vassal”. However, it is possible that the first part of the gloss is meant to read “steadfast/trusty man”, so that the word is only a noun.
boronnoun/adjective. steadfast, trusty man, faithful vassal