Relating to or resembling a sepal, which is the part of a flower that protects the bud.
The word sepaline is used mostly in scientific or technical contexts, like when talking about plants or flowers.
Examples:
The sepaline leaves were green and protective.
The sepaline structure of the flower was very strong.
The sepaline part of the plant was very important.
The sepaline cover kept the flower safe.
The sepaline shielded the delicate flower from harm.
The sepaline petals were like a strong wall around the bud.