IPA: /ˌɛlɛktroʊˈmæɡnɪtɪk/
KK: /ɪˌlɛk.trəʊˈmæg.nə.tɪk/
Relating to or produced by the interaction of electric and magnetic fields.
The electromagnetic waves travel through space at the speed of light.
Electromagnetic → It is formed from "electro-" (from Greek "ēlektron", meaning amber, which is associated with electricity) and "magnetic" (from Greek "magnetis", meaning of Magnesia, a region known for its magnetic stones). The word refers to the physical phenomena associated with electric and magnetic fields.
Think of 'electricity' from 'amber' ('electro-') and 'magnetism' from the region known for magnetic stones. This helps you remember that 'electromagnetic' relates to the forces of electricity and magnetism.
No commonly confused words.