Idiot Fool Affected Foolproof Eslpod Plan Proof Negative

A "fool" is a person, usually a man, who has very poor "judgment" (ability to make good decisions) and often acts in silly, stupid, and uninformed ways. To say that someone is a fool is an "insult" (something that is rude and offensive to another person).

To say that something is "-proof" means that it cannot be affected in a negative way by something. For example, a "waterproof" jacket does not let rain pass through the fabric, so a person wearing a waterproof jacket "remains" (stays; continues to be) dry. A "waterproof" watch continues working even when it is "immersed" (put into; completely surrounded by) water. So something that is "foolproof" cannot be damaged or otherwise affected in a negative way by a fool.

A foolproof object is so well designed and so simple to use that even a fool has to use it correctly-it would be impossible for a fool to break it or use it incorrectly. A foolproof plan is so simple that it is guaranteed to work well, "regardless of" (without being affected by) the foolishness of the person trying to "implement" (make something happen) the plan. In reality, of course, it seems that some fools can "ruin" (destroy) even "seemingly" (apparently; seeming to be) foolproof plans.

Sometime people use the phrase "idiot proof," which is even stronger than "fool proof." An "idiot" is a like a fool, but even "dumber" (less intelligent). So saying that something is "idiot proof" could be offensive, but the meaning is very clear.