Dear Mallory,

one answer to your (interesting) question is that there is no real need to optimize this vocabulary learning at all. Implicit word learning will take place as soon as students are exposed to the foreign language (here: L2 listening). I could not find a meta-study for L2 listening and word learning in the brevity of time, but this is the evidence for L2 reading and implicit word learning. They found that students implicitly learn approximately 15% of the unknown words they encounter.

Swanborn, M. S. L., & de Glopper, K. (1999). Incidental Word Learning While Reading: A Meta-Analysis. Review of Educational Research, 69(3), 261-285

Moreover, while new words are added, already know words will be reinforced and enhanced in quality. So it's all gain and no loss. You were of course asking about a way to control the input of new vocabulary via TikTok, to which I unfortunately have no answer.

Teaching vocabulary demands a unique & creative teaching method. That's possible only when an instructor applies HOTS (Higher Order Thinking Skills) to devise it.

Refer :

Bloom's Taxonomy & Edward De Bono's Lateral thinking.

TikTok can serve as a powerful tool for enhancing vocabulary development among high school ELL (English Language Learner) students by integrating language learning with the platform's dynamic, engaging content. Educators can capitalize on TikTok’s popularity by designing assignments that encourage students to create and interact with content that incorporates targeted vocabulary. For example, students can be tasked with producing short videos that demonstrate the meaning and usage of new words in creative ways, such as using them in sentences, storytelling, or even through skits. This approach allows students to internalize vocabulary more effectively by placing the words within real-life, relatable contexts. By participating in trends or challenges that involve vocabulary, students also gain exposure to the informal, colloquial usage of language, giving them insight into how language is used naturally by native speakers. Teachers can enhance this by creating classroom hashtags, like #LearnWithTikTok or #WordOfTheWeek, where students share their videos and provide feedback on each other’s use of vocabulary.

Additionally, TikTok can foster a multi-sensory learning experience, which is crucial for language acquisition. Teachers can encourage students to explore English-language content on TikTok, where they can interact with videos that include captions, commentary, and various media formats that demonstrate vocabulary through sound, images, and text. This can help ELL students improve both their receptive and productive language skills, as they actively engage with listening and reading tasks while producing their own content. The brevity and immediacy of TikTok videos also align with the principles of spaced repetition, where short bursts of repeated exposure to new vocabulary over time can lead to better retention. Moreover, the platform’s social nature allows students to collaborate, respond to each other’s videos, and provide peer feedback, all of which contribute to creating a vibrant, learner-driven community where language practice becomes a shared, interactive experience.