Where does “ard-earroo” come from?
ard-earroo (Manx) comes from Manx earroo, from Old Irish áirem, from Old Irish ad·rími, from Proto-Celtic rīmā, from Proto-Indo-European h₂rey-, from Proto-Indo-European h₂er- — to fit, to fix, to put together.
ard-earroo (Manx): prime number
Ancestry of “ard-earroo”, step by step
| Step | Language | Word | Meaning |
|---|
| 1 | Manx | earroo | number; census; figure |
| 2 | Old Irish | áirem | — |
| 3 | Old Irish | ad·rími | counts, numbers, computes; records, recounts,... |
| 4 | Proto-Celtic | rīmā | number |
| 5 | Proto-Indo-European | h₂rey- | to count, count out; to arrange |
| 6 | Proto-Indo-European | h₂er- | to fit, to fix, to put together |