IPA: //ʌnˈhiːdɪŋ//
KK: /ʌnˈhidɪŋ/
Not paying attention to something or ignoring it.
He walked past the warning signs, unheeding of the danger ahead.
Unheeding → It is formed from "un-" (meaning not) and "heeding" (from Old English "hēdan", meaning to pay attention to). The word "unheeding" means not paying attention or disregarding something.
Think of 'not' ('un-') paying 'attention' ('heeding') — that's why unheeding means to ignore or not notice something.