The definition of top-heavy is someone or something that has most of its weight at the top and is likely to fall over as a result.(adjective)
A very heavy table top resting on a very small stand that can barely support the weight of the top is an example of a table that would be described as top-heavy.
See top-heavy in Webster's New World College Dictionary
See top-heavy in American Heritage Dictionary 4
adjective top-heav·i·er, top-heav·i·est
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