【Explicit】 , 【express】 , 【specific】 , 【definite】 , 【categorical】 are comparable when applied to statements, utterances, and language and when meaning perfectly clear in significance or reference.
Something is 【explicit】 which is stated so plainly and distinctly that nothing is left to be inferred or to cause difficulty by being vague, equivocal, or ambiguous.
Something is 【express】 which is both 【explicit】 and is uttered or expressed with directness, pointedness, or force.
Something is 【specific】 which is perfectly precise in its reference to a particular thing or in its statement of the details covered or comprehended.
Something is 【definite】 which leaves no doubt as to its reference or to its details or as to what is excluded; 【definite】 , far more than 【specific】 , suggests precise and determinate limitations.
In practice 【specific】 and 【definite】 are often used interchangeably without loss; but 【specific】 may be preferred when the intent is to stress particularization of reference or specification of details, and 【definite】 when it is to emphasize clear limitations; thus, a worker may be given 【specific】 instructions about the sequence in which his tasks are to be performed but a 【definite】 order not to smoke on the job.
【Categorical】 (see also ULTIMATE 2 ) implies explicitness without the least suggestion of a qualification or condition; thus, a 【categorical】 answer is demanded of a person testifying in court when he is compelled to answer yes or no; a 【categorical】 denial is a denial that is complete and contains not the slightest reservations.