Vocabulary acquisition is a fundamental element of mastering the English language, necessitating a comprehensive lexicon that evolves through experiential learning to facilitate accurate comprehension and production of language. The current study examined the impact of Total Physical Response (TPR) tasks on the vocabulary acquisition of Thai primary school students, with a particular focus on the definition of words. It also explored the students' attitudes towards using TPR tasks for vocabulary learning. The TPR tasks were designed to engage three of the human senses--visual, auditory, and tactile--by incorporating multisensory tasks. Employing a mixed-methods research design, the study involved 27 second graders from a primary school in northeastern Thailand. The research methodology utilized three instruments. From a quantitative perspective, the Receptive Word Knowledge Test (RWKT) and the Productive Word Knowledge Test (PWKT) were administered to assess the students' vocabulary knowledge before and after the intervention within a single-group pretest-posttest framework. Qualitatively, a focus group interview was conducted to gain deeper insight into the students' attitudes towards participation in TPR activities. The quantitative data indicated a significant enhancement in both receptive and productive vocabulary knowledge among the participants. Furthermore, the qualitative findings highlighted the advantages of TPR tasks, with students expressing increased enthusiasm and competitive spirit and a shared willingness and pleasure in vocabulary learning through interactive tasks and peer interaction. In conclusion, this study corroborates the efficacy of TPR tasks in significantly advancing Thai primary school students' receptive and productive vocabulary knowledge.