noun. pipefitting that joins two pipes of different diameter.
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.
- reducing agent
Example sentences of the word reducer
1. Noun, singular or mass
Finish this pipe off with a 3-to-4 reducer to form a nice base for attaching the head of your choice to your figure.