Warcraft Encyclopedia: Darnassian

Darnassian is the primary language of night elves. It has both written and spoken equivalents.

Just as the naga, high elves, and blood elves are descended from night elves, so Darnassian bears some resemblance to the Nazja and Thalassian languages. There are, however, strong ideological differences between the night elves and their distant kin. Thus, a linguist must take great care in drawing comparisons between Darnassian and its two cousin languages. Night elves tend to consider such comparisons offensive.

References

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