מְתֻמָּן (Metuman) — octagon
Etymology
The term for an octagon in Hebrew, metuman, was formally established in the late 1930s by the Va'ad HaLashon (The Hebrew Language Council). Historically, the medieval mathematician and philosopher Abraham bar Hiyya had coined the term meshuman (מְשֻׁמָּן) in the 12th century in his foundational work Hibbur ha-Meshihah ve-ha-Tishboret. He followed a consistent morphological pattern for polygons, deriving names from Hebrew numerals, such as meshulash (triangle) and meruba (quadrilateral).
However, meshuman already carried the common meaning of "oily" or "fattened" in Hebrew. To resolve this linguistic ambiguity and provide a distinct, unambiguous term for the geometric shape, the Language Council looked to the Aramaic cognate for eight, tamni (תמני). By applying the same passive participle pattern (M-PO-AL) to the Aramaic root t-m-n, they created metuman.
This move was part of a broader effort to standardize mathematical terminology for the burgeoning Hebrew education system in Mandatory Palestine. While most of Bar Hiyya's 12th-century terms remained in use, metuman stands out as a deliberate modern substitution designed for technical precision, alongside other adjustments like trapez (trapezoid) and the introduction of metzula (polygon).
Key Quotes
"וכן המשובע והמשומן, כל אחד מהם שמו חצוב מן מנין צלעותיו וכן המעושר ולמעלה ממנו." — אברהם בר חייא, חיבור המשיחה והתשבורת, המאה ה-12
"ועד הלשון... החליט, ככל הנראה בגלל שלמילה זאת יש משמעות אחרת, לקבוע תחתיו את המילה מְתֻּמָּן, תוך שימוש במילה הארמית לשמונה, תמני, במקום המילה העברית." — טור המקור, 2026
Timeline
- 12th Century: Abraham bar Hiyya coins meshuman based on the Hebrew root for eight (ש-מ-נ).
- 1920: Isaac Ladizhensky publishes a systematic geometry course, using many medieval terms.
- 1930s: The Hebrew Language Council (Va'ad HaLashon) replaces meshuman with the Aramaic-based metuman.
Related Words
- מְצֻלָּע (metzula) — polygon
- מְשֻׁמָּן (meshuman) — medieval term for octagon; also means oily or fattened.
- מְשֻׁלָּשׁ (meshulash) — triangle
- מְרֻבָּע (meruba) — quadrilateral/square
- מַלְבֵּן (malben) — rectangle