What is "if you know what i mean"

phr. (non-gloss definition Used to allude to something unsaid or hint at hinted at).

"If You Know What I Mean" is a song written and recorded by Neil Diamond. The song is a track from Diamond's 1976 album, Beautiful Noise, and was Diamond's third number one on the Easy Listening chart, where it spent two weeks. "If You Know What I Mean" went to number one for two nonconsecutive weeks and peaked at number eleven on the Billboard Hot 100. Diamond has stated that the song is a "tender recollection" of a relationship in his teens, in which he successfully seduced a significantly older woman.