Questions & Answers about Dekkjamynstrið er gott.
It is a compound noun:
- dekkja- = of tires / tire-
- mynstur = pattern
- -ið = the
So the whole word means the tire tread / the tire pattern.
Icelandic very often builds long nouns this way, where English would use two or three separate words.
Because Icelandic usually writes compound nouns as a single word.
So where English might say:
- tire tread
- tire pattern
Icelandic prefers one compound noun:
- dekkjamynstur
- dekkjamynstrið = the tire tread/pattern
This is very normal in Icelandic and one of the first things English speakers need to get used to.