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Confused by INCI, BHA, humectant, fungal acne, “non-comedogenic”? This bilingual glossary explains 50 essential skincare terms in plain language.
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Shop all verified products →Skincare has its own language, and the jargon stops a lot of people from building a good routine. Here are 50 essential terms, explained simply. Bookmark this and refer back any time. For how the actives work together, see ingredient layering, and the full authentic-skincare guide.
Skin & barrier basics
1. Skin barrier — the outer layer that keeps moisture in and irritants out. Repair it with ceramides.
2. Sebum — the skin’s natural oil.
3. Sebaceous glands — glands that produce sebum.
4. pH — acidity level; healthy skin is slightly acidic (~4.7–5.5).
5. Microbiome — the community of good bacteria living on skin.
6. TEWL (trans-epidermal water loss) — water escaping through a weak barrier.
7. Dehydrated skin — lacking *water* (a condition); different from dry skin (lacking *oil*).
8. Comedone — a clogged pore; open = blackhead, closed = whitehead.
Ingredient types
9. Active — an ingredient that creates a measurable change (e.g. retinol, acids).
10. Humectant — draws in water (e.g. hyaluronic acid, glycerin).
11. Emollient — softens and smooths skin (e.g. squalane).
12. Occlusive — seals moisture in (e.g. petrolatum, shea).
13. Antioxidant — neutralizes free radicals (e.g. vitamin C).
14. AHA — water-soluble acid for surface exfoliation (glycolic, lactic).
15. BHA — oil-soluble acid that works inside pores (salicylic acid).
16. PHA — a gentler exfoliating acid for sensitive skin.
17. Retinoid / retinol — vitamin A derivative for ageing and acne.
18. Niacinamide — vitamin B3; oil control, pores, brightening (guide).
19. Peptides — amino-acid chains that support firmness.
20. Ceramides — barrier-repairing lipids.
21. Centella / Cica — soothing botanical (guide).
22. Azelaic acid — acne + redness + dark spots (guide).
23. Alpha-arbutin — brightening, fades dark spots.
24. Tranexamic acid — targets stubborn pigmentation.
25. Snail mucin — hydrating, repairing K-beauty ingredient.
Concerns & conditions
26. Acne — clogged, inflamed pores (guide).
27. Fungal acne (malassezia folliculitis) — yeast-driven bumps; needs different care than normal acne.
28. Hyperpigmentation — dark patches from excess melanin.
29. PIH (post-inflammatory hyperpigmentation) — dark marks left after acne; common on brown skin.
30. Melasma — hormonal/sun-driven symmetrical patches (guide).
31. Rosacea — chronic facial redness.
32. Keratosis pilaris — rough “chicken skin” bumps on arms.
33. Purging — temporary breakout when starting an active that speeds cell turnover.
34. Breakout / reaction — irritation or clogging from an unsuitable product (not purging).
Product & label terms
35. INCI — the standardized ingredient list on every product.
36. Non-comedogenic — formulated not to clog pores.
37. Fragrance-free vs unscented — free of added scent vs scent-masked.
38. Broad-spectrum — sunscreen protecting from UVA + UVB.
39. SPF — sunburn (UVB) protection rating.
40. PA+ rating — UVA protection level (more + = more protection).
41. Patch test — applying a product to a small area first to check for reaction.
42. Double cleansing — oil cleanser then water-based cleanser (great for sunscreen/makeup).
43. Slugging — sealing the routine with an occlusive overnight.
44. Batch code — manufacturing code used to verify authenticity & expiry (how to check).
45. PAO (period after opening) — the “6M/12M” jar symbol = months usable after opening.
Authenticity terms (Bangladesh)
46. Counterfeit / fake — an illegal copy of a brand product.
47. First copy / replica / master copy — all names for counterfeits (explained).
48. Grey market — genuine product imported through unofficial channels (no warranty, storage unknown).
49. Invoice-verified — matched to its importer invoice to prove origin (what it means).
50. BSTI — Bangladesh Standards & Testing Institution; sets product safety standards.
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