Strong's Definition
from 5074; properly, rejection; by implication, impurity, especially personal (menstruation) or moral (idolatry, incest)
KJV Usage: X far, filthiness, X flowers, menstruous (woman), put apart, X removed (woman), separation, set apart, unclean(-ness, thing, with filthiness)
STEPBible — Tyndale Abridged Hebrew Lexicon
נִדָּה (nid.dah) — impurity. 1) impurity, filthiness, menstruous, set apart 1a) impurity 1a1) of ceremonial impurity 1a2) of menstruation 1b) impure thing (fig.) 1b1) of idolatry, immorality
UBS Dictionary of Biblical Hebrew
noun f · נדה
Unclean
impurity = state in which humans are considered unclean because of a flow of blood or contact with a corpse
LEV 12:2 · LEV 12:5 · LEV 15:19 · LEV 15:20 · LEV 15:24 · LEV 15:25 · LEV 15:25 · LEV 15:25 · LEV 15:26 · LEV 15:26 · LEV 15:33 · LEV 18:19 · NUM 19:9 · NUM 19:13 · NUM 19:20 · NUM 19:21 · NUM 19:21 · NUM 31:23 · EZK 18:6 · EZK 22:10 · EZK 36:17
UBS Dictionary of Biblical Hebrew © United Bible Societies, licensed CC BY-SA 4.0.
Brown-Driver-Briggs Hebrew Lexicon
נִדָּה n.f. impurity (as abhorrent, shunned) of ceremonial impurity
fig. (with allusion to cerem. usage), impure thing
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