Definition

A type of extinct marine animal that had a spiral shell, similar to a squid, and is related to modern cephalopods.

Example

The fossilized ammonoid was discovered in the sedimentary rock.

Conversation

Did you know that an ammonoid is a type of fossil?

Yeah, I've heard of those before! They're really interesting.

I find it fascinating how they lived in the ocean millions of years ago.

Absolutely! It's amazing to think about all the creatures that existed back then.

Synonyms & Antonyms

Root Explanation

Ammonoid is formed from "ammon" (from Latin *ammonis*, referring to the Egyptian god Amun, often associated with ram-like features) and "-oid" (meaning resembling or having the form of). The term ammonoid refers to a group of extinct marine mollusks that have a shell resembling that of the ammonite, which is named after the god Amun due to the coiled shape of their shells resembling ram's horns.

Memory Tip

Think of the god Amun, whose name is linked to the ram-like shape of the ammonoid's shell, helping you remember that ammonoid refers to creatures with a shell resembling that of a ram.

Visually Confused Words