The term 'Nugget, as of Wisdom' can be solved by the crossword solution 'PEARL' (5 letters). A PEARL is a hard, round object produced within the soft tissue of a living shelled mollusk. Pearls are formed when an irritant such as a parasite or a piece of sand enters the mollusk's shell and the mollusk secretes a substance to coat the irritant. Over time, this substance hardens and forms a PEARL. Pearls have been used for centuries as a symbol of wisdom and are often referred to as 'nuggets of wisdom'.