IPA: //ʌnˈtɪltɪd//
KK: /ʌnˈtɪltɪd/
Not slanted or angled; remaining in a straight or upright position.
The picture frame was untilted, perfectly aligned with the wall.
This word originates from the combination of 'un-' (meaning not) and 'tilt' (from Old English 'tyltan', meaning to incline or lean). The word 'untilted' means not inclined or not leaning.
Think of 'not' ('un-') leaning or 'inclining' ('tilt') — that's why untilted means not inclined.