This is the 482nd most frequent Icelandic word.
mikilvægi
Importance.
Here, 'mikilvægi' is a noun meaning 'importance', emphasizing the significant role of health.
Mikilvægi heilsu er oft vanmetið.
The importance of health is often underestimated.
In this sentence, 'mikilvægi' refers to the pertinence or significance of an action, namely learning languages.
Við ræddum um mikilvægi þess að læra nýjar tungumál.
We discussed the importance of learning new languages.
Here, 'mikilvægi' is used to describe the weight or significance of a particular issue or matter being discussed.