Social, economic and cultural transformations of the Polish countryside over the last few dozen years have resulted in the disappearance of many professions, such as, i.a. the profession of an animal castrator, who worked mostly in pig farms. The aim of this paper is to indicate the semantic elements in derivational bases (charaszac, charszowac, czyścic, kastrowac, krasac, miśic, miśkowac) and formal exponents constituting derivatives to name a person who castrates animals (‑acz, ‑aj, ‑ak, ‑ek, ‑nik, ‑ajko, ‑ciel, ‑un, ‑ator, ‑arz, ‑o). Apart from that, the author intends to discuss the geographical range of those derivatives, not only in the borderland region, but in the whole Polish dialect area. Moreover, the paper discusses the issues of lexical, see kras‑ak / mis‑ak, kastrow‑ak / kras‑ak and word-formation variants, see czyszcz‑acz — czyszcz‑ak — czyszcz‑arz — czyśc‑iciel. The analysed material originates in the dialects of the Lesser Poland and Masovia borderland and it was collected in 2008–2011 from 32 villages.