Any process that stops, prevents, or reduces the frequency, rate, or extent of granulocyte macrophage colony-stimulating factor production.
Synonyms:
exact_synonym:
down regulation of granulocyte macrophage colony-stimulating factor production; downregulation of granulocyte macrophage colony-stimulating factor production; negative regulation of GM-CSF production
narrow_synonym:
inhibition of granulocyte macrophage colony-stimulating factor production; negative regulation of granulocyte macrophage colony-stimulating factor biosynthetic process