Made brittle; having become fragile or easily broken.
From brittle + -ed (adjective-forming or past participle suffix). Can function as an adjective describing something that has been made fragile.
Brittled is extremely rare because 'brittle' already works as an adjective, so adding -ed feels redundant—English prefers the shortest form that works, which is why 'brittle' is used rather than 'brittled.'
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