Engaging means charming, and holding your attention. An engaging manner, an engaging speaker, engaging and warm.
It is about the effect on other people rather than any quality in itself: an engaging speaker is one you keep listening to. It is mild praise and slightly formal, and it is one of the safest compliments in a reference.
1adjectiveengagingCharming, and holding your attention.
“Our new history teacher is so engaging that nobody looks at their phone in class.”
engaging is a quality.