Reductor and Reducer

Reducer and reductor are semantically related in gearbox topic. In some cases you can use "Reducer" instead a noun "Reductor", when it comes to topics like gear box, reduction gear.

Reducer noun - A substance capable of bringing about the reduction of another substance as it itself is oxidized; used in photography to lessen the density of a negative or print by oxidizing some of the loose silver.

Reductor and reducer are semantically related in gearbox topic. You can use "Reductor" instead a noun "Reducer", if it concerns topics such as gear box, reduction gear.