This work represents a first step in the direction of reconstructing a diachronic morphology for Romanian. The main resource used in this task is the digital version of Romanian Language Dictionary (eDTLR). This resource offers various usage examples for its entries, citations extracted from popular Romanian texts, which often present diachronic and inflected forms of the word they are provided for. The concept of “word deformation” is introduced and classified into more categories. The research conducted aims at detecting one type of such deformations occurring in the citations ― changes only in the stem of the current word, without the migration to another paradigm. An algorithm is presented which automatically infers old stem forms. This uses a paradigmatic data model of the current Romanian morphology. Having the inferred roots and the paradigms that they are part of, old flexion forms of the words can be deduced. Even more, by considering the years in which the citations were published, the inferred old word forms can be framed in certain periods of time, creating a great resource for research in the evolution of the Romanian language.