Unusual Words
A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon.
What it requires
WCAG 2.0 SC 3.1.3 (AAA) requires a mechanism (glossary, inline definition, expandable abbreviation) for unusual or jargon words. Industry-specific terms ("rolling tackle", "amuse-bouche", "roving tabindex") need a definition path.
For a Shopify storefront the most common application is product-listing copy that uses ingredient or material jargon (a wine site, an art-supply store). A linked glossary or an inline `<dfn>` element each satisfy the criterion.
Common Shopify failure
Wine product page using terms like "tannic", "malolactic", "cuvée" with no glossary link.
How to fix it
Link a glossary page or use `<dfn>` markup with a tooltip definition. AccessComply flags long product copy with high jargon density for merchant review.
Primary source: W3C — WCAG 2.0 Understanding 3.1.3