هُدًى
hudan
guidance
هـدـي
Most Arabic words are built from a small set of root letters — knowing the root helps you recognize related words across the dictionary.
ذَٰلِكَ الْكِتَابُ لَا رَيْبَ فِيهِ هُدًى لِّلْمُتَّقِينَ
This is the Book about which there is no doubt, a guidance for the God-conscious (Quran 2:2)