1690s, from Italian sonata "piece of instrumental music," literally "sounded" (i.e. "played on an instrument," as opposed to cantata "sung"), fem. past participle of sonare "to sound," from Latin sonare "to sound" (from PIE root *swen- "to sound"). The meaning narrowed by mid-18c. toward large-scale works in three or four movements.
fem. word- and name-forming element, from Latin -ina (see -ine (1)), or its identical descendants in Spanish, Portuguese, or Italian. The French form is -ine. As a suffix in royal titles (czarina, etc.) it represents an extension from Latin regina.
<a href="https://www.etymonline.com/word/sonatina">Etymology of sonatina by etymonline</a>
Harper, D. (n.d.). Etymology of sonatina. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/sonatina