Jaques Étienne Gay (b. 1786 Switzerland – 1864) was a Swiss-French botanist, civil servant, collector and taxonomist. His name is associated with plants in standardised botanical nomenclature, e.g. Crocus sieberi J.Gay. He was the most famous of the students of botanist Jean François Aimée Gaudin with whom he began collecting plants at the age of 14. He was married to Rosalie Nillion.
The botanical genus Gaya was named in his honour, as was the species Potamogeton gayi Bennett 1892.
List of botanists by author abbreviation