prudent: having the practical good sense to size up a situation and act wisely in it
The word φρόνιμος (phronimos) describes a person with sound practical sense: the one who reads a real situation and does the sensible thing in it. It points to down-to-earth prudence, the intelligence that shows in what a person decides and does, not the depth of what they know.
This sets it apart from the broader Greek word for wisdom, σοφός, which can reach into skill, learning, and moral or philosophical wisdom, and from συνετός, the person who grasps and connects ideas. This word is narrower and more active: foresight and good judgment worked out in actual decisions. The name for the quality itself is φρόνησις.
Because practical prudence can serve any goal, the word ranges from warm praise to sharp irony. Jesus commends the prudent bridesmaids who bring extra oil and the faithful, prudent servant who is ready for his master, and he even tells his followers to be as prudent as serpents. But the same shrewdness marks the dishonest manager whom the world would applaud for his cleverness, and Paul turns the word against readers who are prudent only in their own eyes.