An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 2 Search : vertex
degree of vertex
  درجه‌ی ِ تارک   
daraje-ye târak

Fr.: degré de vertex   

The → number of → edges incident on the → vertex.

degree; → vertex.

vertex
  تارک   
târak

Fr.: vertex, sommet   

Plural form: vertices.
1) Astro.: A point in the → celestial sphere toward which or from which the common motion of a group of stars is directed.
2) Math.: The → point where two → sides of a → plane figure or an → angle  → intersect.
3) In → graph theory, any of the points of which graphs are formed. Same as → node.

From L. vertex "highest point," literally "the turning point," originally "whirlpool," from vertere "to turn," cognate with Pers. vartidan, gardidan, → version.

Târak, variant târ "top, vertex, head, the middle of the head;" cf. Sogd. târ "summit, forehead;" Yaghnobi tôr(k) "the back of the head;" Yazghulami tur "summit, head;" Proto-Ir. *starH- "to spread," → expand; PIE *ster- "spread, extend."