Appendage and Spicule

Appendage noun - Something that is not necessary in itself but adds to the convenience or performance of the main piece of equipment.

Spicule and appendage are semantically related. In some cases you can replace term "Spicule" with "Appendage", this nouns are similar.

Nearby Words: append, appended, appending

Spicule noun - Small pointed structure serving as a skeletal element in various marine and freshwater invertebrates e.g. sponges and corals.

Appendage and spicule are semantically related. You can use "Appendage" instead a noun "Spicule".