Authority
The authority of a dictionary can be determined by the reputation of its compiler(s)/editor(s), associates and publishers. Generally, a linguist et a philologist helped by experts in pronunciations, etymology, spellings, and various subject fields together produce a dictionary. The authoritativeness of these compilers and the experts can be evaluated on the basis of their qualifications and scholarly contributions in their fields.
The publishing history of particular dictionary also plays an important role in assessing the value of the dictionary. As language undergoes continuous change by adding newly coined and borrowed words and deleting obsolete words, it is essential to revise dictionaries periodically. Thus, a publication which has been revised and updated regularly within a few decades can be considered reliable and dependable.
Again, there are some publishers well-known in the field of lexicography since last two to three centuries. G. & C. Merriam, Funk and Wagnall and McGraw-Hill in United States and Oxford University Press, Longman and Cassell, Cambridge in Britain are some of the notable publishers who specialise in the field of publishing dictionaries. They have published a variety of dictionaries and kept them up to date by bringing new editions at regular intervals. Elsevier and Penguin have also published various subject dictionaries and earned good name in last few decades