. "\"Any process that stops, prevents, or reduces the frequency, rate or extent of the regulated release of acetylcholine.\" [GOC:ef]" . . "negative regulation of acetylcholine secretion" . "down regulation of acetylcholine secretion" . "down-regulation of acetylcholine secretion" . "downregulation of acetylcholine secretion" . . . . . "inhibition of acetylcholine secretion" .