Mach
4 lettersnounrareUpdated June 2026
Definition
Ernst Mach (1838 to 1916), an Austrian physicist and philosopher who introduced the Mach number as a unit of speed relative to the speed of sound, and whose empiricist ideas were foundational to logical positivism.
“Mach's ideas about the relativity of motion influenced a generation of scientists, including the young Einstein.”
Word Game Tips
Wordle
Ends in CH which is uncommon in Wordle, M and A are strong early letters to test
Scrabble
Worth 11 points, the CH combination is valuable and MACH scores well for a four-letter word
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