Boyd’s Bible Dictionary:
Before the captivity the willow was an emblem of joy
(Lev. 23:40; Job 40:22; Isa. 44:4); but in allusion to the captivity, the weeping willow of Babylonia became the poetical type of sorrow (Psa. 137:2). The “brook of willows” (Isa. 15:7), was in the land of Moab, and is called “valley of Arabians” in margin.
Concise Bible Dictionary:
Salix Babylonica
Supposed to be the Salix Babylonica. Its boughs were used at the Feast of Tabernacles, a season of joy; but at the captivity and since, it is a symbol of sorrow. It was on such that the captives hung their harps when in captivity, of which the Psalmist spoke prophetically (Lev. 23:40; Job 40:22; Psa. 137:2; Isa. 15:7; Isa. 44:4). In Ezekiel 17:5 thy word is tsaphtsaphah, supposed by some to be the Arabic safsaf, a willow or osier which grows by the water.
Salix Babylonica
Salix Babylonica
Strong’s Dictionary of Hebrew Words:
Transliteration:
tsaphtsaphah
Meaning:
from 6687; a willow (as growing in overflowed places)