The superlative form of austere; the most stern, strict, or severe, without any luxury or comfort.
From austere plus the superlative suffix -est, which marks the highest degree. This old Germanic ending survives alongside 'most austere' in modern English.
Old English could make superlatives three ways—adding -est (austerest), using 'most' (most austere), or both (most austerest)! Modern English has mostly settled on adding -est for short adjectives, though the double form persists in dialect and archaic writing.
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