From "lăcaș" [house]; Names of the 3 stocks, according to Habenicht: Lăcașu* + the genitive form of the name, with its definite article, of its pipe (e.g. Lăcașu* suflătorului, ~ carabei, and ~ bâzoiului; ➺ NB¹).
NB¹: "Lăcașu" is a form with a "semi-definite" article (Compare Bulgarian кавал (kavàl) / кавалът (kavàlăt [the kavàl]; subject) / кавала (kavàla; [direct] object).
NB²: A "кавал" (kavàl) is a traditional Bulgarian end-blown flute, and not to be confused with the Romanian "caval", which is a pentatonic duct flute).