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Atoms and parts of atoms

alpha particle

noun

the nucleus of a helium atom that is produced by some radioactive substances

anion

noun

an ion with a negative electrical charge

antiparticle

noun

a type of particle in an atom that has the opposite electrical charge to the charge that a normal particle has, although they both have the same mass

atom

noun

the smallest unit of any substance. It consists of a nucleus made of protons and neutrons with electrons travelling around it

atomic

adjective

relating to the atoms in a substance

atomic mass

noun

relative atomic mass

atomic number

noun

the number of protons in the nucleus of an atom

atomic weight

noun

relative atomic mass

cation

noun

an ion that has a positive electrical charge

chain

noun

a part of a molecule consisting of a series of atoms connected in a line

electron

noun

a part of an atom that moves around the nucleus (=centre) and has a negative electrical charge

elementary particle

noun

one of the parts that make up a subatomic particle such as a proton or neutron

fissile

adjective

a fissile atom or element can be separated into parts by nuclear fission

free radical

noun

a molecule that has an extra electron and can react very easily with other molecules. Free radicals sometimes form in the human body and can cause cancer.

God particle

noun

a non-technical name for the Higgs boson

graphene

noun

a material that consists of a layer of carbon that is only one atom thick

Higgs boson

noun

an elementary particle (=an extremely small piece of matter) that could explain where mass (=the amount of matter that something contains) comes from. It is sometimes referred to in non-technical contexts as the God particle.

ion

noun

an atom with an electrical force created by adding or removing an electron

molar

adjective

relating to a mole (=a unit for measuring the number of molecules in a substance)

mole

noun

a unit for measuring the number of molecules in a substance

molecular

adjective

relating to molecules

molecule

noun

the smallest part of an element or compound that is capable of independent existence. It consists of two or more atoms

monomer

noun

a simple molecule that can combine with other molecules to form a polymer

neutrino

noun

a particle that is smaller than an atom and has no electrical charge

neutron

noun

the part of the nucleus of an atom that has no electrical charge

nuclear

adjective

relating to the central part of an atom

nucleus

noun

the central part of an atom, consisting of protons and neutrons

orbit

noun

the path that is taken by an electron around the nucleus of an atom

orbit

verb

to make a circular movement around the nucleus of an atom

particle

noun

an extremely small piece of matter that is part of an atom, for example an electron, proton, or neutron

positron

noun

a particle that is the same size as an electron but has a positive electrical charge

proton

noun

the part of the nucleus of an atom that has a positive electrical charge

quark

noun

a very small unit of matter that the particles of an atom consist of

radical

noun

a group of atoms that are part of a molecule and do not change as a result of a chemical reaction

relative atomic mass

noun

the mass of an atom of a particular chemical element

valence

noun

the valency of an atom

valency

noun

a measurement of the ability of a chemical element to combine with other elements. The measurement is a number that shows how many atoms of the element combine with a single atom of the element hydrogen.

kabaddi

a game in which two teams of seven players take turns to chase and try to touch players on the opposing team

BuzzWord Article

Open Dictionary

Ouch!

a response to a scathing comment or unpleasant situation

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