From Wiktionary, the free dictionary
mažas (“small”) + -yn (“forms adverbs indicating a change toward a condition”)
mažyn
- downward in size; becoming smaller
- Antonym: didyn
2013, Alfonsas Eidintas et al., Lietuvos istorija, Vilniaus universiteto leidykla, page 252:Atkurto ūkininkų ūkio vidutinis dydis ėjo mažyn, iki 6 ha.- The average size of the restored farmers' farm went down to 6 ha.