In reality, they mean the tens of thousands of concealed (often in homes, schools, mosques and hospitals) explosive-laden rockets that are launched at Israelis at a rate that has averaged out at more than one a day over a period of years. In Gaza, there's a major industry churning them out. And many of them are imported from other countries' military industries. Home-made is completely misleading, which is the whole point.
This morning there was, as we reported earlier, a successful intercept by the IDF of yet another Palestinian Arab human bomb. The man, wearing the explosives on his person, was stopped while carrying a lethal package which was (it's not yet clear from the published details of the investigation ) going to be exploded while he was carrying it or handed off to someone else who would explode. Either way, the goal was to kill Israelis in cold blood - as many as possible.
The IDF released the image above a short time ago. It shows an explosive vest made for use by a human bomb and includes 12 explosive devices. If, Heaven forbid, it had slipped through the Israeli defences today, it might have caused horrifying losses.
Think of it the next time you hear the Palestinian Arabs and their amen corner refer to home-made explosives.