building block

American  

noun

building blocks plural

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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Other Word Forms

Noun Inflected Forms

• building blocks
  plural

Etymology

Origin of building block

First recorded in 1840–50

Example Sentences

In a study published in Nature Communications, the researchers found that tubulin, a protein that serves as the building block of microtubules, may help prevent these toxic accumulations.

From Science Daily • Jun. 21, 2026

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

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

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

Trouble, Jesse often declared, was the building block of character.

From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz

Related Words

• constituent
• ingredient