Or the block, niggas standin tight as lemons on the ave
Here, Jay is talking about drug dealers standing on the block — a.k.a. the place where they sell drugs — so long that he likens them to lemons (as in cars which no longer operate and as a result are constantly “standing” or parked in the same spot on a street). Basically, he’s saying the drug dealers never leave their posts to make money. This is imagery is continued in the next line.
He could also be referring to a prison block, I hear prisons are pretty crowded these days…
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