Microbubbles

Part of speech: noun

Definitions

1. Extremely tiny gas-filled bubbles, often injected into the bloodstream to improve medical ultrasound images or deliver drugs
2. Minute bubbles of gas, usually a few micrometres across, employed as contrast agents in imaging or as carriers for therapy
3. Very small gas spheres that are used in diagnostic scanning and targeted treatment because they reflect sound waves clearly

Etymology: "Microbubbles" is the plural of "microbubble," a compound formed from "micro-" and "bubble." The first element, "micro-," comes from Greek "mikros," meaning "small," and has been used in English and other European languages as a combining form to mean something very small or a factor of one millionth. The second element, "bubble," is an older English word for a small globe of gas or air, and it is the sort of everyday term that long predates any scientific use. The compound is a straightforward modern coinage. Once scientists and engineers needed a name for bubbles small enough to be measured in micrometres, attaching "micro-" to the familiar "bubble" gave them a transparent label. The word needs no special story; its meaning is simply the combination of its two parts, a bubble made small.