Simple past tense and past participle of preplan.(verb)
Planned in advance(adjective)
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Use "preplanned" in a sentence
"Plus I think that people will shy away in general from the idea of preplanned bombs."
"If your home has a basement but you do not wish to set up a permanent-type basement shelter, the next best thing would be to arrange to assemble a "preplanned" home shelter."
"A tilt-up storage unit in the best corner of your basement is another method of setting up a "preplanned" family fallout shelter."