These words pertain either to an authoritative statement that someone is to do something or to the giving of knowledgeable advice or guidance. Command and order are the least formal of these words referring to the stated demand of a superior. Of these, command is the more formal and more general; it may pertain to an overall plan that is to be executed, whereas order might pertain more to a limited action or to a detailed part of such a plan: They received headquarters?command to attack at dawn, together with the special orders each unit was to follow. In addition, command is more forceful, peremptory, and less impersonal: Your wish is my command ; a standing order to remain in uniform during off-duty hours. But command can refer to a position of control: the general’s ten-year command of the infantry division.

Directive an injunction are considerably more formal than the foregoing and are much more limited and specific in their application. Injunction now pertains mostly to a legal context, there it indicates a court order which is backed by the threat of strenuous punishment for disobedience. An injunction often takes the form of a command to refrain from a specified action: an injunction that prevented the building contractor from working at night. Directive refers to orders , often detailed at length, which those in command send down through channels to gain the compliance of all affected personnel. Where the previous words can suggest either oral or written statements, directive most often suggests written guidelines for action. The word can seem to apply, euphemistically, to advice that carries no explicit threat of punishment for disobedience; but the rulings of a directive are usually mandatory and beyond appeal: a directive isused to all executives concerning a step-up in production during the next quarter; a battalion’s directive on changes in the dress uniform; the vice-chancellor’s directive on admission procedure.

Direction and instruction both have applications referring to orders that may not be contravened; in this sense both are extremely formal. Direction would suggest a less detailed verbal or written statement than directive ; it is also less forceful and more euphemistic in tone: a direction on staff-appointment practices that was sent down to the personnel department. Often it can apply to informative but mandatory guidelines: the company’s directions concerning the issuance of new share certificates. In the context of orders , instruction stresses that a desired action cannot be done without including the necessary information as part of the command: junior officers awaiting the instructions of the company commander; the judge’s instructions to the jurors; she left detailed instructions to the maid about preparations for the party. When the giving of information is not suggested by the word, it can be even more euphemistic than direction : the sergeant’s instruction to fall out for reveille.

The last pair pertain more often and less formally to the giving of knowledgeable advice or guidance. In the plural, both can indicate a programmatic or diagrammatic plan for a relatively complicated actions that one wishes or chooses to perform. Directions would be more appropriate for a one-time action, instructions for an action one may wish to learn by heart or perform more than once: printed directions for assembling the components of the sound system; instructions for using the electric frying pan. Direction can apply, of course, to information about reaching a place: She asked for directions to get to the railway station. Instruction most commonly relates to an entirely separate context pertaining to teaching and learning.