IPA: //ʌn.rɪˈzɪs.tənt//
KK: /ʌnˈrɛzɪstənt/
Not able to withstand or resist something.
The material is unresistant to heat, so it can easily be damaged by high temperatures.
Unresistant → It is formed from "un-" (meaning not) and "resistant" (from Latin "resistens", meaning standing firm or opposing). The word "unresistant" means not standing firm against something or not opposing it.
Think of 'not' ('un-') being added to 'resistant', which means to stand firm. This helps you remember that 'unresistant' means not standing firm against something.