|Easton's Bible Dictionary|
(1.) Denotes Mount Hermon in Deuteronomy 4:48; called Sirion by the Sidonians, and by the Amorites Shenir (Deuteronomy 3:9). (see HERMON.)
(2.) The Greek form of Zion (q.v.) in Matthew 21:5; John 12:15.
Int. Standard Bible Encyclopedia
si'-un (si'on; Seon):
(1) A name given to Mt. Hermon in Deuteronomy 4:48. The name may mean "protuberance" or "peak," and may have denoted the lofty snow-covered horn of the mountain as seen from the South. It may, however, be a scribal error for Sirion, the name by which the mountain was known to the Zidonians. Syriac takes it in this sense, which, however, may be a correction of the Hebrew. It is possible that this name, like Senir, may have applied to some distinct part of the Hermon Range.
(2) Mt. Sion.
Sion (9 Occurrences)
Matthew 21:5 Tell ye the daughter of Sion, Behold, thy King cometh unto thee, meek, and sitting upon an ass, and a colt the foal of an ass. (KJV WBS)
John 12:15 Fear not, daughter of Sion: behold, thy King cometh, sitting on an ass's colt. (KJV WBS YLT)
Romans 9:33 As it is written, Behold, I lay in Sion a stumblingstone and rock of offence: and whosoever believeth on him shall not be ashamed. (KJV WBS YLT)
Romans 11:26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob: (KJV WBS YLT)
Hebrews 12:22 But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels, (KJV WBS)
1 Peter 2:6 Wherefore also it is contained in the scripture, Behold, I lay in Sion a chief corner stone, elect, precious: and he that believeth on him shall not be confounded. (KJV WBS)
Revelation 14:1 And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads. (KJV WBS YLT)
Deuteronomy 4:48 from Aroer, which is on the edge of the valley of the Arnon, even to Mount Sion (the same is Hermon), (WEB KJV JPS ASV BBE DBY WBS YLT NAS)
Psalms 65:1 Praise waiteth for thee, O God, in Sion: and unto thee shall the vow be performed. (KJV)