1) The selection of head-words. This problem can also be subdivided into several questions:
How far a dictionary should admit the historical
Selection between scientific and technical terms
Whether a dictionary should cover all the words of the language, including neologisms, nonce-words, slang, non-assimilated borrowings, foreign words, etc.
Should a dictionary be perceptive and prohibitive (should dictionary-makers attempt to improve and stabilize the vocabulary according to the best classical samples and advise the readers on preferable usage)
Should the frequency of the usage of words be taken into consideration (this is a modern criterion)
2) The arrangement and contents of the vocabulary entry:
a) Which of the selected units have the right to a separate entry and which are to be included under one common head-word.
b) Should the derivatives with suffixes –er, -ing, -ness, -ly be included in a dictionary
c) Differentiation and the sequence of various meanings of a polysemantic word.
d) A synchronic dictionary should also show the distribution of every word.
3) The principles of sense definitions in a unilingual dictionary
a) there are two main types of definitions linguistic – they are only concerned with words as speech material.