IPA: /ˈstɛpˌlædə/
KK: /ˈstɛpˌlædər/
A type of ladder that can stand on its own, with steps and a platform at the top, used for reaching high places.
I used a stepladder to change the light bulb in the ceiling.
Stepladder is formed from "step" (from Old English "stæpe", meaning a place to put the foot) and "ladder" (from Old English "hlæder", meaning a structure for climbing). The word describes a ladder designed with steps for climbing up or down safely.
Think of a 'step' as a place to put your foot and a 'ladder' as a structure for climbing — together, a stepladder is a climbing structure with steps.
No commonly confused words.