<p><strong>noun</strong></p><ul><li>British: a plural of placebo; a substance having no pharmacological effect but given merely to satisfy a patient who supposes it to be a medicine.</li><li>a substance having no pharmacological effect but administered as a control in testing experimentally or clinically the efficacy of a biologically active preparation.</li><li>Roman Catholic Church: the vespers of the office for the dead; so called from the initial word of the first antiphon, taken from Psalm 114:9 of the Vulgate.</li></ul>