がん

壁(かべ)にがんと頭(あたま)を打(う)ちました。

I hit my head hard against the wall. {with a thump, with a thud, with a bang, , hard (hit, scold, etc.), severely, marking (on a card or tile for the purpose of cheating), card marking, tile marking, alteration}

車(くるま)が壁(かべ)にがんと突進(とっしん)したようです。

It seems like the car crashed into the wall with a bang. {with a thump, with a thud, with a bang, , hard (hit, scold, etc.), severely, marking (on a card or tile for the purpose of cheating), card marking, tile marking, alteration}

ドアにがんと顔(かお)をぶつけて顔(かお)が腫(は)れました。

I hit my face hard against the door and it swelled up. {with a thump, with a thud, with a bang, , hard (hit, scold, etc.), severely, marking (on a card or tile for the purpose of cheating), card marking, tile marking, alteration}

がんと頭(あたま)を打(う)ったところがだんだんプックリと腫(は)れてきました。

The place where I hit my head hard is gradually starting to swell noticeably. {with a thump, with a thud, with a bang, , hard (hit, scold, etc.), severely, marking (on a card or tile for the purpose of cheating), card marking, tile marking, alteration}

酔(よ)ってフラフラと歩(ある)いていたら転(ころ)んで、前歯(まえば)をがんと地面(じめん)にぶつけた。

I was walking around drunkenly and fell over, hitting my front teeth hard on the ground. {with a thump, with a thud, with a bang, , hard (hit, scold, etc.), severely, marking (on a card or tile for the purpose of cheating), card marking, tile marking, alteration}