Where does “phototachometer” come from?

phototachometer (English) comes from English photo, from English photography, from French photographie, from Ancient Greek φωτο-, from Ancient Greek φῶς, from Proto-Hellenic pʰáos, from Proto-Indo-European bʰéh₂os, from Proto-Indo-European bʰeh₂-.

phototachometer (English): A tachometer that measures revolutions by optical sensing

Definitions

  1. A tachometer that measures revolutions by optical sensing

Ancestry of “phototachometer”, step by step

phototachometer traces back through two separate lines of ancestry.

via English photo

StepLanguageWordMeaning
1EnglishphotoA photograph; A photo finish; To take a...
2EnglishphotographyThe art and technology of producing images on...
3Frenchphotographiephotography; photograph
4Ancient Greekφωτο-
5Ancient GreekφῶςAttic form of φᾰ́ος
6Proto-Hellenicpʰáos
7Proto-Indo-Europeanbʰéh₂os
8Proto-Indo-Europeanbʰeh₂-to shine, glow light; to speak, say
9Proto-Indo-Europeanbʰeh₂-s-ri-

via English tachometer

StepLanguageWordMeaning
1EnglishtachometerA device for measuring the revolutions per minute...
2EnglishmeterA device that measures things; A parking meter or...
3Frenchmètremetre/meter; first-person singular present...
4Latinmetruma measure
5Ancient Greekμέτρονsomething used to measure: measure, rule, weight;...
6Ancient Greek-τρονForms instrument nouns
7Proto-Hellenic-tronForms instrument nouns from verb stems
8Proto-Indo-European-tromForms nouns denoting a tool or instrument
9Proto-Indo-European-tḗrDerives agent nouns from verbs, denoting someone...
Every word from Proto-Indo-European bʰeh₂-s-ri-