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disconcerting vs. concerning

disconcerting

[dis-kuhn-sur-ting] / ˌdɪs kənˈsɜr tɪŋ /

adjective

disturbing to one's composure or self-possession; upsetting, discomfiting.
confusing, usually in the face of something totally unexpected; perplexing.

concerning

[kuhn-sur-ning] / kənˈsɜr nɪŋ /

preposition

relating to; regarding; about.

We attended a discussion concerning foreign aid.

adjective

causing concern, worry, or anxiety.

The increase in unlicensed practitioners is concerning.
The more concerning elements of the sport were swept under the rug.