מְאוּרָה mᵉʼûwrâh

Meaning

something lighted, i.e. an aperture; by implication, a crevice or hole (of a serpent)

In the King James Version: den.

Derivation: feminine passive participle of H215 (אוֹר);

Where it is used

• Isaiah 11:8 The infant will play by the cobra’s den, and the toddler will reach into the viper’s nest.