precursor

Everyday

1. Something that came before a later thing and led to it or helped it develop: «The abacus was a precursor of the calculator.» tree →
2. A sign or event that comes before something else: «a precursor to a storm». tree →
3. (science) A substance from which another substance is made in a chemical reaction or in the body. tree →

In the lessons

In history and technology lessons we trace precursors: older inventions, animals or ideas that came first. In science a precursor is a starting chemical. Phrases: «a precursor of», «a precursor to», «an early precursor».

Examples

• The penny-farthing was a precursor of the modern bicycle. tree →
• Telegrams were a precursor to text messages. tree →
• Some dinosaurs were precursors of birds. tree →
• Dark clouds were the precursor to a big storm. tree →
• The Greek Olympics were a precursor of today's Games. tree →
• In plants, some chemicals are precursors of colours in leaves. tree →
• The first computer games were simple precursors of the games we play now. tree →

Note

Countable: a precursor, precursors. Use «precursor of» or «precursor to». It is formal; in everyday talk you can say «forerunner» or «early version». From Latin for «a runner who goes ahead».