Atomic warhead and Fission bomb

Atomic warhead noun - The warhead of a missile designed to deliver an atom bomb.

Fission bomb and atomic warhead are semantically related in nuclear bomb topic. In some cases you can use "Fission bomb" instead a noun phrase "Atomic warhead", when it comes to topics like atomic bomb.

Fission bomb noun - A nuclear weapon in which enormous energy is released by nuclear fission (splitting the nuclei of a heavy element like uranium 235 or plutonium 239).

Atomic warhead and fission bomb are semantically related in nuclear bomb topic. You can use "Atomic warhead" instead a noun phrase "Fission bomb", if it concerns topics such as atomic bomb.