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to poke; to push
授業中、友達が私を小突いた。
During the lecture, a friend poked my side to get my attention.
芸人が舞台で相方の脇腹を小突いている。
The comedian is poking his partner in the ribs on stage for laughs.
兄は妹がぼーっとしていると、からかうように小突く。
My older brother playfully pokes his sister whenever she spaces out.