Dan. beorn n. “man”
A noun for “man” that developed from the blending of primitive ᴹ✶besnō “man” and ᴹ✶berō “valiant man, warrior” > ber(n)ō (Ety/BER, BES). The simplest explanation is that ᴹ✶besnō > beznō > bernō, where first the [s] voiced to [z] before the nasal [n] and then the resulting [z] becoming [r]. The similarity of this word to ᴹ✶berō could have led it to develop into ber(n)ō as well. From there, the [e] broke into the diphthong [eo] before the liquid [r] and then the final vowel vanished.
References ✧ Ety/BER, BES
|ᴹ✶ber(n)ō > beorn||[bernō] > [beornō] > [beorn]||✧ Ety/BER|
|ᴹ✶besnō > beorn||[besnō] > [beznō] > [bernō] > [beornō] > [beorn]||✧ Ety/BES|