thumb — Parts of the Body thumb /θʌm/ noun CEFR A2 The short, thick finger at the side of your hand. “The baby was sucking her thumb.” Related words in this scene walknailrunjumptallbodyarmleghandfootshoulderfingertoekneeelbowwristankleneckbackcheststomachhipskinboneholdstrongshortpalmheelwaistthighfist Practice this word Create worksheet