كَاذِبَةٍ

A word in the Arabic language will either be 1) a verb or 2) a noun or 3) a particle – كَاذِبَةٍ is a noun

A noun may either be 1) Definite or indefinite 2) Masculine or feminine 3) Singular, dual or plural 4) Nominative, accusative or genitive

كَاذِبَةٌ is the natural state of this definite noun and it changes to كَاذِبَةٍ due to: 1) a preposition that precedes it or 2) a possessed noun that precedes it or 3) it’s a noun of dependent declension a) نَعْتٌ / صِفَطٌ adjectives b) التَّوْكِيْدُ emphatic c) المَعْطُوْفٌ conjunction d) البَدَلُ synonym

A liar

To lie, say what is not a fact, lie to, falsely invent, tell lies about or against, fabricate a lie, relate a lie, say a falsehood, be wrong, be cut off, deceive, disappoint the expectation of

Surah/Below is the only verse in the holy Quran containing the feminine, active participleكَاذِبَةٍ
Verse
96-16A lying, sinful forelockنَاصِيَةٍ كَاذِبَةٍ خَاطِئَةٍ