# plethysmometer

> English word · Noun

## Definitions
1. Any instrument designed to measure small changes in volume, usually via the displacement of water

## Etymology
From Ancient Greek πληθυσμός (plēthusmós, “increase”) + -meter.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/plethysmometer