The term "vegetable" generally means the edible parts of plants. The definition of the word is traditional rather than scientific, however. Therefore the usage is somewhat arbitrary and subjective, as it is determined by individual cultural customs of food selection and food preparation.
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Mental retardation is a generalized, or triarchic, disorder, characterized by subaverage cognitive functioning and deficits in two or more adaptive behaviors with onset before the age of 18. Once focused almost entirely on cognition, the definition now includes both a component relating to mental functioning and one relating to the individual's functional skills in their environment.
Shovels vs Retards, 
