(literally) for a dam to break and water to burst forth / (figuratively) to burst forth (e.g. tears, words, a crowd)

(idiomatic) let the water carry it away, wipe the slate clean

dam / prevent / stop up

weir, dam

a dike or levee for containing water

to flow / to release / to cancel / to flush (something) down the toilet / to play (music) / (usually in the passive) to exert influence over someone's immediate actions

flowing, running, draining / sink, drain, basin / draining floor (in a bathhouse) / washing the clients' backs in bathhouses, or someone who does so

begin; start; initiate; originate

Alternative spelling of 初めて

conjunctive form of 始める (hajimeru) [ichidan]