What does the cryptic crossword clue "Philosopher somewhat impervious to iconoclasm (5)" mean?

The definition is "Philosopher". The wordplay uses a hidden word. Hidden in "philosopher somewhat imperviouS TO IConoclasm" The answer is STOIC.

Philosopher somewhat impervious to iconoclasm (5)

Guardian Cryptic #29465 | 1 Down | 2024-08-19 flower