also: ガイガーカウンター
Geiger counter
A device that detects and measures ionizing radiation. The full term ガイガー計数管 is technical; ガイガーカウンター is more common in general use.
We used a Geiger counter to measure the radiation level.
Standard technical term for a Geiger counter.
Common loanword spelling from English 'Geiger counter', widely used in everyday contexts.
From German 'Geiger' (after Hans Geiger) + 計数管 (けいすうかん, 'counter tube'). The alternative form ガイガーカウンター is directly from English 'Geiger counter'.