venal
VEE-nuladjMeaning willing to be bribed; open to doing wrong for money
Memory hook VEND-AL: pay him like a VENDING machine. Drop a coin in his hand and the guard opens the gate for anyone, like a vending machine. He is venal.
The venal guard let anyone through the gate for a gold coin.
In context The old courts were notoriously venal: a rich man could buy any verdict he liked, while a poor one could not even get a hearing.
Similar bribable, corruptible, mercenary, crooked
Opposite incorruptible, honest, upright
From Latin venalis, “for sale,” from venum (sale), the same root as vend.