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

In its primordial form, liberalism was a political belief that the building block of society is the individual—an idea tethered loosely to the Christian notion that every single human being contains a divine spark.

From The Wall Street Journal • Apr. 10, 2026

Before the clash, there was a sense that a positive performance in Madrid could be used as a building block for Tudor before a crucial game at Liverpool in the Premier League this weekend.

From BBC • Mar. 10, 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 would be lovely to cuddle up beside her while Georgie sat nearby, building block towers and pretending not to listen.

From "The Old Willis Place" by Mary Downing Hahn

Related Words

• constituent
• ingredient