con·cern / kənˈsərn/ • v. [tr.] 1. relate to; be about: the story concerns a friend of mine | (be concerned with) this fable is concerned with forgiveness and redemption. ∎  be relevant or important to; affect or involve: they should not pry into what does not concern them. ∎  (be concerned with) regard it as important or interesting to do something: I was mainly concerned with making something that children could enjoy. ∎  (be concerned in) formal have a specific connection with or responsibility for: the organs concerned in digestion and in blood-making. ∎  (concern oneself with) interest or involve oneself in: we need not concern ourselves with the semantics of this language.2. worry (someone); make anxious: you must not concern yourself about me.• n. 1. anxiety; worry. ∎  a cause of anxiety or worry: safety concerns.2. a matter of interest or importance to someone: oil reserves are the concern of the Energy Department. ∎  (concerns) affairs; issues: Aboriginal concerns.3. a business; a firm.PHRASES: as (or so) far as —— is concerned as regards the interests or case of ——: the measures are irrelevant as far as inflation is concerned.to whom it may concern a formula placed at the beginning of a letter or document when the identity of the reader or readers is unknown.

concern †discern; relate to XV; engage the attention of XVI; pass. be interested, involved XVII. — (O)F. concerner or late L. concernere sift, distinguish, in medL. have respect or reference to, f. CON- + cernere sift (cf. CERTAIN). Somewhat earlier in prp. concerning (XV) in uses leading to its use as prep., prob. modelled on a similar use of F. concernant.
Hence concern sb. XVI.