If your income rises above a certain threshold, your tax rate also rises.
… we still hadn't grasped that we had crossed a threshold where it no longer mattered what passport you carried, that you were young and loved, … or that you were a noncombatant. —Paul Salopek, National Geographic, April 2008
As we speak, the very worst of humanity is on the threshold of acquiring the most powerful weapons in history—this is a fear and a consideration to be taken very seriously. —Charles Krauthammer, New Republic, 29 Apr. 2002
We thought that we were on the threshold of an age of space travel. But the greatest impact of the trip to the moon was on how we view the Earth. —Suzannah Lessard, Wilson Quarterly, Summer 2001
: a point or place of beginning or entering <Ralph had a scary feeling he was on the threshold of adventure. — Beverly Cleary, The Mouse and the Motorcycle>
Medical Definition of THRESHOLD
: the point at which a physiological or psychological effect begins to be produced (as the degree of stimulation of a nerve which just produces a response or the concentration of sugar in the blood at which sugar just begins to pass the barrier of the kidneys and enter the urine) <below the threshold of consciousness><the threshold of pain><a high renal clearance threshold>—called also limen