Definition of moellon in English:

moellon

Pronunciation /ˈmwɛlɒn/

noun

(also moëllon)
  • A dark wax or grease used in curing leather; = "degras".

Origin

Late 19th century. From French moellon, alteration (probably after moelle marrow and -on, diminutive suffix) of moleau from mou, mol soft + -eau. Perhaps compare earlier moelline.