Sæll means happy or content. It’s one of the most common ways to greet someone and works well both between good friends and in a professional setting.
sæll
sæl

Longer form

The longer form of sæll is either “be happy” or “be happy and blessed”. Strangely enough, the order of “be” and “happy” can change whether it is thought of as a hello or a goodbye.
  • Hello:
    • Sæll
    • Sæll vertu
    • Vertu sæll og blessaður
  • Goodbye:
    • Vertu sæll
    • Vertu sæll og blessaður

Plural

Using the plural to one person 😎

If you’re addressing a close friend and you want to seem cool and casual, you can say sælir (the plural form) instead of sæll. It makes it sound like you are addressing them like a group (or that you’re talking down to them, as a joke of course).