Aril and Vellum

Aril noun - Fleshy and usually brightly colored cover of some seeds that develops from the ovule stalk and partially or entirely envelopes the seed.

Vellum and aril are semantically related. In some cases you can use "Vellum" instead a noun "Aril".

Vellum noun - Fine parchment prepared from the skin of a young animal e.g. a calf or lamb.

Aril and vellum are semantically related. Sometimes you can use "Aril" instead a noun "Vellum".