godan verb (-su), transitive verb
ignore what one hears; let something go in one ear and out the other; pay no attention to
Used when someone hears something but deliberately does not take it seriously or react to it. Often implies passive disregard rather than active confrontation.
彼の嫌味はいつも聞き流している。
I always let his sarcastic remarks go in one ear and out the other.
大事な話だから聞き流
This is important, so please don't just ignore it.