IPA: //ʌnˈɛntərpraɪzɪŋ//
KK: /ʌnˈɛntərpraɪzɪŋ/
Not willing to take risks or try new things; lacking initiative or ambition.
His unenterprising attitude kept him from pursuing new job opportunities.
Unenterprising → It is formed from "un-" (meaning not) and "enterprising" (from the root "enterprise" which comes from Old French *entreprendre*, meaning to undertake). The word "unenterprising" means not willing to undertake new ventures or lacking initiative.
Think of 'not' ('un-') being added to 'undertaking' ('entreprendre') — that's why unenterprising describes someone who is not willing to take on new challenges.