also: びレそん
expression
not completely unthinkable; not impossible
Internet slang abbreviation of 微粒子レベルで存在している (exists at the subatomic particle level). Used humorously to say something is extremely unlikely but not absolutely zero. Often appears in the pattern 可能性が微レ存.
彼が遅刻しない可能性は微レ存だ。
The possibility that he won't be late is not completely unthinkable.
宝くじが当たる可能性が微レ存。
There's a tiny, almost nonexistent chance of winning the lottery.
微粒子 means 'fine particle'; 微レ存 is a playful abbreviation of 微粒子レベルで存在している, turning a scientific phrase into slang.
Internet slang abbreviation of 微粒子レベルで存在している (exists at the subatomic particle level). The レ is a katakana abbreviation of 粒 (りゅう) from 粒子.