the.com/thousand

means The number 1,000 — ten hundreds, the first big round milestone where quantities stop being countable at a glance.

from Traces back to Old English 'þūsend,' from a Proto-Germanic root, itself likely built from two older Indo-European pieces meaning roughly 'swollen' or 'strong' (the same root behind words like 'tumor' and 'thigh') and 'hundred.' So, etymologically, a thousand may once have meant something like 'a swollen hundred' — a hundred grown fat. Fittingly, the word itself ballooned to describe the first number that feels like too many to hold in your head at once.