Wet/Dry Ratio
Definition
The balance between the processed (wet) signal and the unprocessed original (dry) signal when using an effect. A higher wet ratio means more of the effect is audible; a lower ratio preserves more of the original character.
In Simple Terms
The balance between the effect and the original sound. 100% wet is all effect, no original. 100% dry is no effect at all. Most of the time, you want a subtle blend — enough effect to feel it without drowning the original.
In Practice
A reverb on a snare drum set at 15% wet keeps the drum natural and present while adding a subtle sense of room depth.