doorstep; step up to an entrance
Rare term for a step or raised platform at an entrance, such as a doorstep or the step leading into a traditional Japanese house. More commonly expressed as 上がり段 (あがりだん) or 上がり框 (あがりがまち).
I sat down on the doorstep of the old house.
Compound of 上り (のぼり, 'going up') + 段 (だん, 'step'). The reading のぼりだん is a rare variant of the more common 上がり段 (あがりだん).