marked by qualities giving the power to produce an intended effect; "written propaganda is less efficacious than the habits and prejudices...of the readers"-Aldous Huxley; "the medicine is efficacious in stopping a cough"
feeling or showing worry or solicitude; "concerned parents of youthful offenders"; "was concerned about the future"; "we feel concerned about accomplishing the task at hand"; "greatly concerned not to disappoint a small child"
involved in or affected by or having a claim to or share in; "a memorandum to those concerned"; "an enterprise in which three men are concerned"; "factors concerned in the rise and fall of epidemics"; "the interested parties met to discuss the business"
in relation (or in regard) to; especially as in the phrases; "as far as x is concerned"; "where x is concerned"
occurring in the same period of time; "a rise in interest rates is often contemporaneous with an increase in inflation"; "the composer Salieri was contemporary with Mozart"