The Proto-Semitic word ʾaḫ
Word ʾaḫ
Meaning brother

Comments
Kaye, Alan S. "Christopher Ehret. Reconstructing Proto-Afroasiatic (Proto-Afrasian): Vowels, Tone, Consonants, and Vocabulary", University of California 1995

Other words that might be of interest
ʔns ‘person, man’, ʾab ‘father’, ʾin(a)š ‘man’, ʾam ‘maid, girl’, nišw ‘woman’, bar ‘son’, bin ‘son’, walad ‘boy, child’