hydramnios

noun

hy·​dram·​ni·​os hī-ˈdram-nē-ˌäs 

variants also hydramnion

-ˌän 

: excessive accumulation of the amniotic fluid

called also polyhydramnios

hydramniotic

hī-ˌdram-nē-ˈät-ik 

adjective