# Glossary

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Glossary This section translates recurring supplement terms into plain English. It is meant to reduce the friction created by label jargon, clinical-sounding wording, certification language, and marketing phrases that make ordinary supplement questions feel harder than they need to be. Supplement glossary definition The Supplement Explained glossary is a plain-English reference for label terms, supplement-form wording, dose math, testing claims, safety-limit language, and marketing phrases that often confuse shoppers. Each term is designed to answer the definition first, then show where the term matters on a real supplement label. How should you use this glossary? Use it when a term on a label changes the buying decision: serving size changes dose math, CFU changes probiotic comparisons, elemental magnesium changes mineral comparisons, third-party testing changes quality confidence, and upper limit changes safety context. What makes a glossary term useful? A useful definition should be short enough to understand quickly, specific enough to compare products, and connected to the broader guide where the term affects real supplement choices. How This Section Connects To The Rest Of The Site Definitions are not isolated. Each glossary entry links back to the ingredient, quality, basics, safety, or compare page where the term actually matters. Plain English comes first. The goal is to reduce cognitive load, not to perform expertise. Start Here Bioavailability Useful when supplement-form marketing leans on absorption claims and you want to know when that actually changes the decision. CFU Useful when probiotic marketing is leaning heavily on a giant number and you want to know what that number can and cannot tell you. Daily Value Useful when %DV looks authoritative but you are not sure how much it should shape the buying decision. Elemental calcium Useful when calcium labels look stronger or weaker than they really are because the compound and the actual mineral amount are not the same thing. Elemental magnesium Useful when magnesium labels list glycinate, citrate, oxide, or threonate and you need the actual magnesium amount. Excipient Useful when the label question is really about fillers, binders, coatings, or why non-active ingredients still affect the product experience. Heavy metals Useful when a supplement page mentions lead, cadmium, mercury, arsenic, contaminants, COAs, or clean-label testing. NSF Certified for Sport Useful when an athlete, coach, parent, or drug-tested competitor needs a stronger quality signal than a generic tested claim. Other Ingredients Useful when the confusing part of the label sits in the ingredient list rather than in the main Supplement Facts box. Proprietary blend Useful when a label groups ingredients together and you want to know what is still visible and what is being hidden. Serving size Useful when a label hides the real dose behind two capsules, one scoop, or several gummies. Third-party testing Useful when a label says tested, certified, verified, or clean and you need to know whether that claim is specific enough to trust. Upper limit Useful when a nutrient page mentions too much vitamin D, zinc, magnesium, selenium, iron, or another nutrient. USP Verified Useful when a label uses the USP mark and you want to know what it does and does not prove. Use This Hub By Intent Decode absorption language Useful when supplement-form marketing leans on absorption claims and you want to know when that actually changes the decision. Decode probiotic numbers Useful when probiotic marketing is leaning heavily on a giant number and you want to know what that number can and cannot tell you. Understand percentages better Useful when %DV looks authoritative but you are not sure how much it should shape the buying decision. Understand calcium compound-vs-mineral labels Useful when calcium labels look stronger or weaker than they really are because the compound and the actual mineral amount are not the same thing. Understand magnesium compound-vs-mineral labels Useful when magnesium labels list glycinate, citrate, oxide, or threonate and you need the actual magnesium amount. Decode non-active ingredients Useful when the label question is really about fillers, binders, coatings, or why non-active ingredients still affect the product experience. Decode contaminant testing language Useful when a supplement page mentions lead, cadmium, mercury, arsenic, contaminants, COAs, or clean-label testing. Decode sport-focused certification Useful when an athlete, coach, parent, or drug-tested competitor needs a stronger quality signal than a generic tested claim. Decode the label below the facts panel Useful when the confusing part of the label sits in the ingredient list rather than in the main Supplement Facts box. Decode hidden blend math Useful when a label groups ingredients together and you want to know what is still visible and what is being hidden. Decode label math first Useful when a label hides the real dose behind two capsules, one scoop, or several gummies. Decode testing and certification claims Useful when a label says tested, certified, verified, or clean and you need to know whether that claim is specific enough to trust. Decode safety-limit language Useful when a nutrient page mentions too much vitamin D, zinc, magnesium, selenium, iron, or another nutrient. Decode USP verification Useful when a label uses the USP mark and you want to know what it does and does not prove. Go back to full label reading Useful when the confusing term is only one part of a wider Supplement Facts panel problem. Go back to dosage context Useful when the term makes sense, but the real decision is still about what counts as a realistic daily amount. Readers Usually Go Next How to Read a Supplement Label Best next click when the confusing term came from the Supplement Facts panel and you want the bigger label-reading workflow. How to Read Dosage vs Serving Size Useful when the term is only one piece of a bigger dosage, capsule-count, or serving-burden question. What Third Party Tested Means Useful when glossary terms start pointing toward verification, certificates, seals, or testing claims. USP vs NSF Useful when you need to compare common third-party quality programs without treating every seal as identical. How to Read a COA Useful when the next step is checking whether a testing document actually answers the contaminant or potency question. Magnesium Return to the owner page when elemental magnesium, form choice, and serving size need a full ingredient-level decision. Vitamin D Return to the owner page when upper-limit language, lab testing, and high-dose labels need more context. Probiotics Return to the owner page when CFU terms start pointing toward strain, evidence, and side-effect questions.