noun

• The state of being singular, distinct, peculiar, uncommon or unusual.
• An unusual action or behaviour.
• A point where all parallel lines meet.
• A point where a measured variable reaches unmeasurable or infinite value.
• (mathematics) The value or range of values of a function for which a derivative does not exist.
• (obsolete) Anything singular, rare, or curious.
• (obsolete) Possession of a particular or exclusive privilege, prerogative, or distinction.
• Celibacy, singleness (as contrasted with marriage).
• (technology) The technological singularity.
• (physics) Ellipsis of gravitational singularity: a point or region in spacetime in which gravitational forces cause matter to have an infinite density; associated with black holes. [(physics) A location where the quantities that are used to measure the gravitational field become infinite in a way that does not depend on the coordinate system.]
• (sometimes capitalized) Ellipsis of technological singularity: a hypothetical turning point in the future, the culmination ever accelerating technological progress, when human history as we have known it ends, and a strange new era begins. For some writers, the catalyst is superhuman machine intelligence. [A hypothetical future event in human history caused by the ever-increasing ability of new technology to speed up the rate at which new technology is developed.]