Having been given or increased in height; raised up or elevated (now archaic or rare usage).
Past participle of the verb 'height' (to make high or raise), which was used in Middle and Early Modern English though largely replaced by 'heighten' in contemporary usage.
The verb 'height' was once common enough that Shakespeare used it, but 'heightened' eventually took over—a fascinating example of how English gradually consolidates multiple verbs into single dominant forms.
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