Boomerang and Nerve gas

Boomerang noun - A curved piece of wood; when properly thrown will return to thrower.

Nerve gas and boomerang are semantically related. In some cases you can use "Nerve gas" instead a noun "Boomerang".

Nerve gas noun - A toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system.

Boomerang and nerve gas are semantically related. Sometimes you can use "Boomerang" instead a noun phrase "Nerve gas".