IPA: /ʌnˈsteɪbli/
KK: /ʌnˈsteɪbli/
In a way that is not steady or secure, often leading to changes or difficulties.
The tower swayed unstably in the strong winds, making everyone nervous.
Unstably → It is formed from "un-" (meaning not) and "stable" (from Latin "stabilis", meaning standing firm or steady) and the suffix "-ly" (meaning in a manner). The word "unstably" means in a manner that is not steady or firm.
Think of 'not' ('un-') being added to 'steady' ('stable') to remember that 'unstably' means not steady.