Answer in Details
To save the universe, Lord Shiva compassionately drank the poison. However, instead of swallowing it, he held it in his throat to prevent it from harming himself or the world. Due to the potency of the poison, Shiva's throat turned blue, and hence, he became known as Neelkanth—'Neel' meaning blue and 'Kanth' meaning throat.
This act symbolizes Lord Shiva's willingness to absorb negativity and suffering for the well-being of the world, highlighting his role as a protector and savior. It also teaches the importance of sacrifice, compassion, and self-control.