Inertia vs. Mass

The property of a body that resists any change to its uniform motion; equivalent to its mass.

(figuratively) In a person, unwillingness to take action.

(medicine) Lack of activity; sluggishness; said especially of the uterus, when, in labour, its contractions have nearly or wholly ceased.

That property of matter by which it tends when at rest to remain so, and when in motion to continue in motion, and in the same straight line or direction, unless acted on by some external force; - sometimes called vis inertiæ. The inertia of a body is proportional to its mass.

Inertness; indisposition to motion, exertion, or action; lack of energy; sluggishness.

Example: ‘Men . . . have immense irresolution and inertia.’;

Lack of activity; sluggishness; - said especially of the uterus, when, in labor, its contractions have nearly or wholly ceased.

a disposition to remain inactive or inert;

Example: ‘he had to overcome his inertia and get back to work’;

(physics) the tendency of a body to maintain is state of rest or uniform motion unless acted upon by an external force

a tendency to do nothing or to remain unchanged

Example: ‘the bureaucratic inertia of the various tiers of government’;

a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force

Example: ‘the power required to overcome friction and the inertia of the moving parts’;

resistance to change in some other physical property

Example: ‘the thermal inertia of the oceans will delay the full rise in temperature for a few decades’;

Inertia is the resistance of any physical object to any change in its velocity. This includes changes to the object's speed, or direction of motion.

(physical) Matter, material.

A quantity of matter cohering together so as to make one body, or an aggregation of particles or things which collectively make one body or quantity, usually of considerable size

(obsolete) Precious metal, especially gold or silver.

(physics) The quantity of matter which a body contains, irrespective of its bulk or volume. It is one of four fundamental properties of matter. It is measured in kilograms in the SI system of measurement.

(pharmacy) A medicinal substance made into a cohesive, homogeneous lump, of consistency suitable for making pills; as, blue mass.

(medicine) A palpable or visible abnormal globular structure; a tumor.

(bodybuilding) Excess body weight, especially in the form of muscle hypertrophy.

(proscribed) weight

A large quantity; a sum.

(quantity) Large in number.

Bulk; magnitude; body; size.

The principal part; the main body.

A large body of individuals, especially persons.

Example: ‘The mass of spectators didn't see the infraction on the field.’; ‘A mass of ships converged on the beaches of Dunkirk.’;

(in the plural) The lower classes of persons.

Example: ‘The masses are revolting.’;

(Christianity) The Eucharist, now especially in Roman Catholicism.

(Christianity) Celebration of the Eucharist.

The sacrament of the Eucharist.

A musical setting of parts of the mass.

(transitive) To form or collect into a mass; to form into a collective body; to bring together into masses; to assemble.

(intransitive) To have a certain mass.

Example: ‘I mass 70 kilograms’;

To celebrate mass.

Involving a mass of things; concerning a large quantity or number.

Example: ‘There is evidence of mass extinctions in the distant past.’;

Involving a mass of people; of, for, or by the masses.

Example: ‘Mass unemployment resulted from the financial collapse.’;

The sacrifice in the sacrament of the Eucharist, or the consecration and oblation of the host.

The portions of the Mass usually set to music, considered as a musical composition; - namely, the Kyrie, the Gloria, the Credo, the Sanctus, and the Agnus Dei, besides sometimes an Offertory and the Benedictus.

A quantity of matter cohering together so as to make one body, or an aggregation of particles or things which collectively make one body or quantity, usually of considerable size; as, a mass of ore, metal, sand, or water.

Example: ‘If it were not for these principles, the bodies of the earth, planets, comets, sun, and all things in them, would grow cold and freeze, and become inactive masses.’; ‘A deep mass of continual sea is slower stirredTo rage.’;

A medicinal substance made into a cohesive, homogeneous lump, of consistency suitable for making pills; as, blue mass.

A large quantity; a sum.

Example: ‘All the mass of gold that comes into Spain.’; ‘He had spent a huge mass of treasure.’;

Bulk; magnitude; body; size.

Example: ‘This army of such mass and charge.’;

The principal part; the main body.

Example: ‘Night closed upon the pursuit, and aided the mass of the fugitives in their escape.’;

The quantity of matter which a body contains, irrespective of its bulk or volume.

To celebrate Mass.

To form or collect into a mass; to form into a collective body; to bring together into masses; to assemble.

Example: ‘But mass them together and they are terrible indeed.’;

the property of a body that causes it to have weight in a gravitational field

(often followed by `of') a large number or amount or extent;

Example: ‘a batch of letters’; ‘a deal of trouble’; ‘a lot of money’; ‘he made a mint on the stock market’; ‘it must have cost plenty’;

an ill-structured collection of similar things (objects or people)

(Roman Catholic Church and Protestant Churches) the celebration of the Eucharist

a body of matter without definite shape;

Example: ‘a huge ice mass’;

the common people generally;

Example: ‘separate the warriors from the mass’; ‘power to the people’;

the property of something that is great in magnitude;

Example: ‘it is cheaper to buy it in bulk’; ‘he received a mass of correspondence’; ‘the volume of exports’;

a musical setting for a Mass;

Example: ‘they played a Mass composed by Beethoven’;

a sequence of prayers constituting the Christian eucharistic rite;

Example: ‘the priest said Mass’;

join together into a mass or collect or form a mass;

Example: ‘Crowds were massing outside the palace’;

occurring widely (as to many people);

Example: ‘mass destruction’;

gathered or tending to gather into a mass or whole;

Example: ‘aggregate expenses include expenses of all divisions combined for the entire year’; ‘the aggregated amount of indebtedness’;

the celebration of the Christian Eucharist, especially in the Roman Catholic Church

Example: ‘we went to Mass’;

a particular celebration of the Eucharist

Example: ‘he pontificated at three Christmas Masses’;

a musical setting of parts of the liturgy used in the Mass

Example: ‘Bach's B minor Mass’;

involving or affecting large numbers of people or things

Example: ‘a mass exodus of refugees’; ‘the film has mass appeal’;

assemble or cause to assemble into a single body or mass

Example: ‘both countries began massing troops in the region’; ‘clouds massed heavily on the horizon’;

Mass is both a property of a physical body and a measure of its resistance to acceleration (rate of change of velocity with respect to time) when a net force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies.