The term "overstimulate" refers to a state where an individual is excessively stimulated, causing stress, anxiety, and fatigue. The antonyms for the word overstimulate include understimulate, dull, enervate, and bore, which refer to a state where there is a lack of stimulation or excitement. When an individual is understimulated, the brain and body are not adequately engaged, leading to a sense of boredom and lack of motivation. Dullness refers to a lack of excitement or interesting stimuli, causing lethargy and disinterest. Enervate refers to a lack of energy or vitality, rendering the individual weakened and uninterested. Lastly, to bore means to fail to engage, excite or interest someone, leading to a feeling of disinterest and detachment.