1Describes something falling, colliding, or dropping with a heavy thud or bang.
彼は疲れ果てて、玄関でばったり倒れてしまった。
He was so exhausted that he collapsed with a thud right at the entrance.
本棚が倒れて、本がばったり床に散らばった。
The bookshelf tipped over and the books scattered across the floor with a bang.
強い風で看板がばったり倒れた。
A strong gust of wind knocked the sign down with a crash.
2Describes running into someone unexpectedly, by chance — commonly used as 'ばったり会う' (to bump into someone).
駅前で高校時代の友人にばったり会った。
I ran into an old high school friend in front of the station.
買い物中に元同僚とばったり出くわして驚いた。
I was surprised to bump into a former coworker while shopping.
こんな場所で先生にばったり会うとは思わなかった。
I never expected to run into my teacher in a place like this.
3Describes something that was ongoing coming to an abrupt end or stop.
去年からの連絡がばったり途絶えてしまった。
The contact we'd had since last year suddenly stopped.
順調だった売り上げが不況でばったり止まった。
Sales, which had been going well, abruptly halted due to the recession.
毎週来ていた常連客の足がばったり途絶えた。
The regular customer who used to come every week suddenly stopped showing up.