Definition of explainer in US English:

explainer

noun

  • 1A person who explains a concept, topic, situation, etc.

    ‘an excellent teacher and explainer’
    ‘scientists often aren't the best explainers’
    1. 1.1 A statement, article, or video that provides an explanation of a concept, topic, situation, etc.
      ‘if you're confused, Reuters has a quick explainer on how the Italian election works’
      ‘can you give us an explainer of what sub-prime means?’
      as modifier ‘learn more about gravity and how it affects all objects in space with this terrific explainer video’

Pronunciation

explainer

/ikˈsplānər//ɪkˈspleɪnər/