(n.) The act of putting under water; submersion\.

baptism breaking water burial cadence catenary concavity crash dive de-escalation debasement decline decurrence degradation demotion depression descent detrusion diminution dip dipping displacement dive dousing draft droop duck ducking dunking engulfment hauling down hollowness immergence immersion inundation lapse lowering reduction running dive sag sinkage sinking slump souse sousing stationary dive submersion subsidence surfacing swag thrusting under