النَّاصِيَةِ

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

النَّاصِيَةُ is the natural state of this definite noun and it changes to النَّاصِيَةِ 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

Forelock

To seize one by the forelock, get the mastery over, get hold of

Surah/Below is the only verse in the holy Quran containing the feminine, active participleالنَّصِيَةِ
Verse
96-15Nay! if he ceases not, We will surely catch him by the forelockكَلَّا لَئِنْ لَّمْ يَنْتَهِ لَنَسْفَعًا بِالنَّاصِيَةِ