Question
Is Hanuman an avatar of Lord Shiva?
Answer
Yes. Lord Hanuman is Rudra avatar of Lord Shiva as per shiva puran. Mother of Lord Hanuman Pleased Vayu devata and Lord Shiva to have son. Vayu devata gave her boon of son and Lord Shiva was asked to give son who is exactly like him. So Lord Shiva granted Anjanimata boon that his 11th Rudra will take birth as her son and Lord Hanuman born.
In hanuman chalisa
Shankar suvan kesri Nandan
Tej pratap maha jag vandan
Meaning
As a descendant of Lord Shankar, you are a comfort and pride of Shri Kesari. With the lustre of your Vast Sway, you are propitiated all over the universe.
Reference
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