The Difference between "tentacle" and "antenna"

The Difference between “tentacle” and “antenna”

• “Tentacle” is used usually when talking about animals like an octopus or squid.
  Tentacles are usually like arms to an animal.
• “Antenna” is used when talking about insects and other bugs. Antennae (the plural) are not usually equivalent to legs or arms - they are their own way for an animal or insect to feel things, almost like whiskers on a cat.
• “Antenna” in other uses refers to something that picks up a signal. The things on top of old televisions or that extend from radios and cars are also called antennas. (Note that this type of “Antenna” has the plural form of “antennas”, not “antennae”!)

Reference:一大神回答