In linguistics|lang=en terms the difference between phonetics and lexicography

is that phonetics is (linguistics) the study of the physical sounds of human speech, concerned with the physical properties of speech sounds (phones), and the processes of their physiological production, auditory reception, and neurophysiological perception, and their representation by written symbols while lexicography is (linguistics) the scholarly discipline of analyzing and describing the semantic, syntagmatic and paradigmatic relationships within the lexicon (vocabulary) of a language and developing theories of dictionary components and structures linking the data in dictionaries.

As nouns the difference between phonetics and lexicography

is that phonetics is (linguistics) the study of the physical sounds of human speech, concerned with the physical properties of speech sounds (phones), and the processes of their physiological production, auditory reception, and neurophysiological perception, and their representation by written symbols while lexicography is the art or craft of compiling, writing and editing dictionaries.