Jacob's ladder
noun
Ja·cob's ladder ˈjā-kəbz- 
1
: any of a genus (Polemonium) of herbs of the phlox family that have pinnate leaves, a bell-shaped corolla, and a several-seeded capsule
especially : a perennial herb (P. caeruleum) with bright blue or occasionally white flowers
2
: a marine ladder of rope or chain with wooden or iron rungs
Word History
Etymology
from the ladder seen in a dream by Jacob in Genesis 28:12
First Known Use
1733, in the meaning defined at sense 1