尼德霍格（Nidhogg），在北欧神话中，是一只盘据在世界之树（Yggdrasil）的底部，不断啃蚀着其根部的一条邪龙。尼德霍格有多种写法：Nidhogg、Nidhoggr、Nithhogg, Nidhögg、Nidhöggr、Nithhöggr、Nídhöggr、Nithhoggr、Nidhhogg、Níðhögg、Niðhoggr、Níðhoggr、Nídhögg、Hidhaegg或Nidhhoggr。英语化为：Nidhoggur。丹麦语中可能以Nidhug或Nidhog表示。名字的意思有「恐怖啃蚀者」（The Dread Biter）、「恶意」（Malice Striker）。

In Norse mythology, Níðhöggr (Malice Striker, often anglicized Nidhogg) is a dragon who gnaws at a root of the world tree, Yggdrasil. In historical Viking society, níð was a term for a social stigma implying the loss of honor and the status of a villain. Thus, its name might refer to its role as a horrific monster or in its action of chewing the corpses of the inhabitants of Náströnd: those guilty of murder, adultery, and oath-breaking, which Norse society considered among the worst possible crimes.