Flagellum and Tendril

Flagellum noun - A lash-like appendage used for locomotion (e.g., in sperm cells and some bacteria and protozoa).

Tendril and flagellum are semantically related. In some cases you can use "Tendril" instead a noun "Flagellum".

Tendril noun - Slender stem-like structure by which some twining plants attach themselves to an object for support.

Flagellum and tendril are semantically related. Sometimes you can replace term "Flagellum" with "Tendril", this nouns are similar.