Geographical names are long-lasting, transcending centuries and, at times, millennia. Historical and social processes manifest in the general development of language and changes in the lexicon (archaisms and innovations). This process also impacts the stability of the form of geographical names, causing them to change gradually.

R. Yuzbashov refers to toponyms that have undergone form changes as “distorted toponyms” and identifies three types of distortion:

1. Toponyms with altered meanings,

2. Toponyms that have lost their meaning,

3. "Mute" toponyms.

In our opinion, the term “distortion” does not comprehensively cover toponyms that have undergone changes (e.g., phonetic transformations). V.A. Zhuchkevich uses the term “transformation” in this context. We consider it appropriate to use the term “altered toponyms.” In most cases, toponyms undergo distortion or phonetic change.

Toponyms Derived from Archaic Words

These toponyms are altered due to phonetic adaptations in line with the later development of language. Restoring the original form of ancient toponyms is exceedingly difficult. Sometimes, toponyms that have long lost their meanings are replaced by similar-sounding words through folk etymology.

Toponyms Originating from Foreign Words

Altered toponyms can be classified into three groups:

1. Distorted toponyms: Names distorted due to sound or word omission. This primarily arises from the "economy" trait observed in speech.

2. Phonetically altered toponyms: In these toponyms, sounds are replaced or rearranged.

3. Abbreviated toponyms: It is essential to differentiate between distorted and abbreviated toponyms.

The compilation of contemporary and historical toponyms of any country, region, or area is regarded as that region’s toponymic fund. Occasionally, the term “toponymic bank” is used to describe the toponymic fund. Compiling all of Azerbaijan’s geographical names and creating a fundamental toponymic fund is a matter of state importance. The works of ancient authors mention numerous names of cities, villages, fortresses, and rivers (e.g., Muğan, Qəbələ, Şabran, etc.). Since these settlements have been destroyed, their names have transitioned from the active toponymic fund to the passive fund and are referred to as passive toponyms.Passive toponyms emerge when a geographical object ceases to exist or when its name is changed (the old name transitions to the passive fund). Sometimes, when a toponym moves to the passive fund, it leaves traces in the active fund. For instance, a toponym may move to the passive fund as the name of a settlement but continue to exist as the name of another object (e.g., ruins, a spring, a valley, etc.).R. Yuzbashov describes identifying the existence of one name based on another as “toponymic forecasting.” This principle holds great significance in the study of historical geography. Studying passive toponyms, like active ones, carries substantial scientific importance.To prepare a toponymic dictionary, a toponymic glossary is first compiled. The glossary used to prepare the toponymic dictionary of the Azerbaijan SSR can serve this purpose. However, this book does not include settlement names that have transitioned to the passive fund. Existing literature is insufficient to compile a comprehensive toponymic dictionary of the Azerbaijan SSR. Such a dictionary can only be compiled after the creation of the republic's toponymic fund.An encyclopedic dictionary of Azerbaijan-origin geographical names can also be compiled. Apart from R.M. Yuzbashov’s article, “The Main Issues of Azerbaijani Toponymography,” the theoretical aspects of Azerbaijani toponymic dictionary studies (the author uses the term toponymography in the sense of “toponymic dictionary studies”) have not been specifically investigated to date.

Keywords: toponyms,transformation, dictionary,active,possive