To debilitate is defined as to weaken, make ill or destroy.(verb)
When an illness wears you down and makes you ill, this is an example of a time when the illness debilitates.
See debilitate in Webster's New World College Dictionary
See debilitate in American Heritage Dictionary 4
transitive verb de·bil·i·tat·ed, de·bil·i·tat·ing, de·bil·i·tates
Origin: Latin dēbilitāre, dēbilitāt-
Origin: , from dēbilis, weak; see bel- in Indo-European roots.
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