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monorhinous

American  
[mon-uh-rahy-nuhs] / ˌmɒn əˈraɪ nəs /
Also monorhinal

adjective

Zoology.
  1. having a single, median nostril, as the cyclostomes.


Etymology

Origin of monorhinous

1900–05; mono- + -rhinous < Greek -rhinos -nosed, adj. derivative of rhīs, stem rhin- nose; -ous