From what I've read, that's the very first word, in Proto Indo-European. All other words in all other PIE-based languages have that as a base. Things to note about that word:
1. short;
2. no "i" sound at the end.
Hence "tel-schwa-seen", as I've been saying...
(BTW, "tele" is also from Greek, meaning "distance". All the good compounds are from Greek or Latin...)