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

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

As any sports psychologist can tell you, it’s a fundamental building block for success.

From Los Angeles Times • Feb. 14, 2026

A 30-second hello builds immediate rapport — it turns strangers into friendly faces and makes a building, block, or street feel safer and more human.

From Salon • Jan. 27, 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