【Forbid】 , 【prohibit】 ,  【enjoin】 ,  【interdict】 ,  【inhibit】 ,  【ban】  are comparable when meaning to debar a person from using, doing, or entering or to order something not be used, done, or entered.

【Forbid】  is the more direct and familiar,  【prohibit】  , the more formal or official; they do not widely differ in their essential implications, for they both imply the exercise of authority or the existence of conditions which prevent with similar imperativeness. However,  【forbid】 carries so strong a connotation of expected obedience that it is preferred when the order is that of one in authority (as a parent, a master, an employer, or a physician).

When circumstances absolutely debar,  【forbid】 is also preferred.

【Prohibit】 has been used for so long in reference to laws, statutes, and regulations that it tends to connote a less despotic exercise of authority and to suggest restraints imposed for the good of all or for the sake of orderly procedure.

【Enjoin】  (see also COMMAND ) is a legal term implying a judicial order forbidding a particular action.

【Interdict】 implies prohibition by authority, usually civil or ecclesiastical authority, typically for a given time and for a salutary purpose (as the maintenance of neutrality or the prevention of the spread of disease) or as an exemplary punishment.

【inhibit】 implies the imposition of restraints or restrictions that amount to prohibitions, not only by authority but also by the exigencies of the time or situation.

In psychological use  【inhibit】 suggests the restraints imposed by inner psychological impediments and conflicts or by the interaction of human will with cultural and social factors of the environment which cause one to suppress certain thoughts or desires before they can find full expression.

【Ban】 carries an implication of legal or social pressure as the source of prohibition and with it a strong connotation of condemnation or disapproval.