building block

American  

noun

1. block.

2. one of a set of cube-shaped blocks used by children to make simple constructions.

3. a basic element or component.

   the building blocks of proteins.

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building block British  

noun

1. a block of stone or other material, larger than a brick, used in building

2. a component that fits with others to form a whole

   standardized software building blocks

3. another name for (the child's toy) block

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Etymology

Origin of building block

First recorded in 1840–50

Example Sentences

It will be a building block and a key ingredient in every new “unicorn” — a company with a valuation of at least $1 billion.

From MarketWatch • Apr. 21, 2026

"This Picasso initiative is one more building block so that one day Alzheimer's will be nothing more than a bad memory," the foundation's head Olivier de Ladoucette said, the AFP news agency reported.

From BBC • Apr. 14, 2026

That causes the molecule to crack into hydrogen and ethylene, the basic building block of plastics such as polyethylene.

From The Wall Street Journal • Apr. 5, 2026

In test tube studies, bone forming cells quickly moved into the structured hydrogel and began producing collagen, a key building block of bone.

From Science Daily • Mar. 3, 2026

It’s just one little building block, but they’re about to be surprised by the result.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel

Related Words

• constituent
• ingredient