にゅっとsuddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)

人(にん)が物陰(ものかげ)からにゅっと現(あらわ)れました。

A person suddenly appeared from behind the object. {suddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)}

運転(うんてん)手(しゅ)が窓(まど)からにゅっと顔(かお)を出(だ)して駐車(ちゅうしゃ)した。

The driver suddenly stuck his face out of the window and parked. {suddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)}

犬(いぬ)が窓(まど)から首(くび)をにゅっと出(だ)して外(そと)の景色(けしき)を楽(たの)しんでいる。

The dog is suddenly sticking its head out of the window, enjoying the view outside. {suddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)}

水槽(すいそう)の中(なか)をじっと見(み)ていたら、チンアナゴがにゅっと出(で)てきました。

As I was staring intently into the aquarium, a garden eel suddenly emerged. {suddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)}

家(いえ)の中(なか)に置(お)いてある植木鉢(うえきばち)の土(ど)から虫(むし)がにゅっと出(で)てきて驚(おどろ)いてしまった。

I was surprised when a bug suddenly came out of the soil in the potted plant that was inside the house. {suddenly (appear, stick out), abruptly, unexpectedly, looming (e.g. out of the dark), (stand) still and expressionless, imposingly, suddenly (stand up)}