Nucleus
'njuːkliəs
Definitions
3 meaningsThe central and most important part of something, forming the basis for its activity and growth.
'njuːkliəs
The central and most important part of an object, movement, or group, forming the basis for its activity and growth.
The company's research and development department is the nucleus of its innovative efforts.
💡 Simply: Imagine a band! The *nucleus* of the band is the lead singer and guitarist - the most important part. Everything else revolves around them. It’s the central point, or the key piece around which everything else comes together. For example, the *nucleus* of an argument.
👶 For kids: The most important part of something, like the center of a group or idea.
More Examples
The city's cultural center acts as a nucleus for artistic events.
The team's star player is the nucleus of their offense.
How It's Used
"The nucleus of the protest was a group of students."
"The nucleus of the political party consisted of experienced strategists."
A specialized, usually spherical body within a cell, containing the cell's chromosomes and responsible for the control of its growth and reproduction.
'njuːkliəs
A part of a cell that controls its activities.
The nucleus of a cell contains the DNA.
💡 Simply: Imagine a little office inside your body's cells. That office is the *nucleus*. It's like the control center, telling the cell what to do, like where to go, when to grow, and even when to have kids (by dividing!).
👶 For kids: The boss of the cell! It's the part that tells the cell what to do.
More Examples
Damage to the nucleus can disrupt cellular function.
Scientists study the nucleus to understand how cells work.
How It's Used
"The cell's nucleus contains the genetic material."
"The nucleus houses the chromosomes."
The positively charged central core of an atom, containing the protons and neutrons, and almost all the mass.
'njuːkliəs
The positively charged central core of an atom, consisting of protons and neutrons and containing nearly all of the atomic mass.
Nuclear fission involves splitting the nucleus of an atom.
💡 Simply: Inside every atom is the *nucleus*. It's the tiny, super-heavy center of the atom. Like the sun in our solar system, it’s the middle part and holds everything together. When we talk about *nuclear* power or weapons, we're talking about what happens to these centers.
👶 For kids: The tiny middle part of an atom that's super heavy!
More Examples
The nucleus of the atom is made up of protons and neutrons.
Scientists are working to understand the forces that hold the nucleus together.
How It's Used
"The atomic nucleus is extremely dense."
"Nuclear reactions involve the nucleus of atoms."
From Latin *nucleus* meaning 'kernel, little nut', ultimately from the Proto-Indo-European root *k(e)ru- meaning 'hard substance'. It was first used in biology to describe the central structure of a cell, then later applied to atomic physics.
The term 'nucleus' was first applied in biology to describe the cell's central component in the 19th century, and later adapted for atomic physics.
Memory tip
Think of the nucleus of an atom - it's the core. Similarly, the nucleus of something else is its core or center of activity.
Word Origin
"kernel, little nut"