IPA: //ʌnˈbæl.əstɪd//
KK: /ʌnˈbæl.əstɪd/
Not stabilized or made steady by a weight that keeps something balanced.
The ship was unballasted, causing it to sway dangerously in the rough seas.
Unballasted → It is formed from "un-" (meaning not) and "ballast" (from Middle English *balast*, meaning a heavy material used to provide stability). The word "unballasted" means not having ballast or lacking stability.
Think of something that is 'not' stable ('un-') because it lacks the heavy material ('ballast') that provides support.