Any process that activates or increases the frequency, rate or extent of endosomal vesicle fusion.
Synonyms:
exact_synonym:
positive regulation of endosome vesicle fusion; up regulation of endosomal vesicle fusion; up regulation of endosome vesicle fusion; upregulation of endosomal vesicle fusion; upregulation of endosome vesicle fusion
narrow_synonym:
activation of endosomal vesicle fusion; activation of endosome vesicle fusion