from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A sentence with three clearly defined parts of equal length, usually independent clauses.
- n. The symbol ⁝, a colon with three dots instead of two.
from The Century Dictionary and Cyclopedia
- n. In ancient prosody and rhetoric, a period consisting of three cola.
From Ancient Greek τρικωλος (trikolos, "having three parts") (Wiktionary)
tri- + colon (Wiktionary)