Olfactory derives from the past participle of the Latin olfacere ("to smell"), which was formed from the verb olēre ("to give off a smell") and facere ("to do"). Olfactory is a word that often appears in scientific contexts (as in "olfactory nerves," the nerves that pass from the nose to the brain and contain the receptors that make smelling possible), but it has occasionally branched out into less specialized contexts. The pleasant smell of spring flowers, for example, might be considered an "olfactory delight." A related word, olfaction, is a noun referring to the sense of smell or the act or process of smelling.