Morpheme
-o(u)r
Type
suffix
Denotation
Latin abstract noun suffix
Etymology
Latin -or (genitive -ōris)
Evidence
ardor, ardour, clamor, clamour, decor, error, favor, favour, fluor, fluorspar, honor, horror, languor, liquor, odor, pallor, rancor, rancour, rigor, rigour, sapor, splendor, splendour, squalor, stupor, tenor, terror, timorous, torpor, tremor, tumor, valor, vigor
Notes
British English favors -our, American English favors -or