Questions & Answers about Luftlommen er synlig i krummen.
The ending -en marks the definite form, so luftlommen means the air pocket. Compare:
en luftlomme = an air pocket
luftlommen = the air pocket
Norwegian often adds definiteness to the end of the noun instead of using a separate word like English the.
Yes, possibly. The last part, lomme, is a feminine noun, and in Bokmål many feminine nouns can take either a feminine definite ending -a or the common-gender ending -en, depending on style and preference.
So you may see both:
luftlomma
luftlommen
Both can be correct in Bokmål. -en often looks a bit more conservative or bookish; -a can feel more natural in many speakers' everyday usage.