Haplorhini

Etymology
From +, referring to the lack of a rhinarium (a wet nose, which is found in many mammals, including strepsirrhine primates).

Usage notes
The spelling with a single r, which was the one originally used (in Pocock 1918), has been modified by some taxonomists to have a double rr following rules of derivation in Ancient Greek (specifically, in a compound word the initial r- is automatically doubled after a vowel). Both spellings are in use in the scientific literature.