TOEFL IELTS stiff Definition Rigid or not easily bent; severe or formal in manner. Example "After the workout, his muscles felt stiff and sore." Sign in to save TOEFL PDF — $25 IELTS PDF — $25 ← sticky stiffen → Study tips featuring "stiff" TOEFL Academic Vocabulary: Study by Topic Boost Your IELTS Writing With Precise Vocabulary Related words TOEFL brighten GRE abash GRE abate GRE abbreviate GRE abbreviation SAT abdicate GRE abduct SAT abet GRE abhor GRE abide SAT abject TOEFL ablaze