precursor

2 definitions • 3 examples

something that happened or existed before another thing, especially if it either developed into it or had an influence on it:

Sulphur dioxide is the main precursor of acid rain.

Biological research has often been a precursor to medical breakthroughs.

something that comes before another and may lead to it or influence its development:

Opponents fear this would be a precursor to development of the entire canyon.