Glossing
The provision of brief meaning supports for selected words inside or alongside a reading text — typically as marginal notes, footnotes, inline parentheses, or hover tooltips in digital materials. Glosses lower the lexical threshold of a text without rewriting it, letting learners process unfamiliar items in context rather than breaking off to consult a dictionary.
Forms
Three placements dominate. Marginal glosses sit in a side column next to the line containing the target word. Footnote glosses gather at the bottom of the page, reached by superscript markers. Inline glosses appear in parentheses immediately after the word, the most disruptive but the most accessible option for low-proficiency readers. Digital materials add a fourth option — pop-up or hyperlinked glosses revealed on click or hover, which preserve text appearance and let learners self-select support.
L1 versus L2 glosses
Whether to gloss in the learner's first language or in the target language is the most studied question in the literature. Jacobs, Dufon and Fong (1994) found that English-speaking learners of Spanish recalled more from glossed than unglossed texts on immediate measures, with no consistent advantage for either L1 or L2 glosses. Ko (2012) likewise found L1 and L2 glosses equally effective for vocabulary gains among Korean university learners, even though learners themselves preferred L2 glosses. A 2024 meta-analysis by Kim, Lee and Lee confirms a small advantage for glossing overall, with no robust difference between L1 and L2 placement once proficiency is controlled.
Effects on reading and vocabulary
Glossing improves comprehension on immediate measures and raises incidental vocabulary acquisition compared to unglossed reading, especially for words that recur in the text. Gains on delayed measures are smaller and more variable, suggesting glosses help during reading but require subsequent retrieval practice to consolidate.
Design implications
Materials writers selecting items for glossing typically target words above the assumed coverage level — beyond a learner's working frequency band — and avoid glossing words inferable from context, since over-glossing removes the lexical inferencing that drives long-term acquisition. Sensible density sits below 5–10% of running words.
References
- Jacobs, G. M., Dufon, P., & Fong, C. H. (1994). L1 and L2 vocabulary glosses in L2 reading passages: Their effectiveness for increasing comprehension and vocabulary knowledge. Journal of Research in Reading, 17(1), 19–28.
- Ko, M. H. (2012). Glossing and second language vocabulary learning. TESOL Quarterly, 46(1), 56–79.
- Kim, H. S., Lee, J. H., & Lee, H. (2024). The relative effects of L1 and L2 glosses on L2 learning: A meta-analysis. Language Teaching Research, 28(1).