Proto-MSA *naḫrīr- ‘nose’ goes back to PS *naḫīr- ‘nostriľ (v. SED I No. 198)
PS
*naḫīr- - nostril
(SED I No. 198; Kogan 2011: 221)
The reconstructed vocalic pattern is based on Akk., Hbr., Arm. and rather supported by MSA *naḫrīr--; cf., however, -u- in Arb. nuḫ(a)rat- and Jud. nḫwr.