stepping_stone has definitions from the field of geology
1
[ noun ] (geology) a stone in a marsh or shallow water that can be stepped on in crossing

Used in print

(Helen Hooven Santmyer, "There Were Fences"...)

The street was unpaved and rose steeply toward the center ; it was mud in wet weather and dust , ankle-deep , in dry , and could be crossed only at the corner where there were stepping_stones .

Related terms

rock

2
[ noun ] any means of advancement

Examples

"the job was just a stepping stone on his way to fame and riches"

Related terms

means

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