Bio Lexicon

Look up any biology term for definitions. Hundreds of definitions with pronunciations, examples, and hints — plus true-or-false quizzes across topics. Free revision app.

Bio Lexicon puts a complete biology dictionary in your pocket. Whether you are revising for an exam, preparing a lesson, or simply curious about a term you came across, this app gives you everything you need to understand it properly.

Every one of the 557 entries includes a clear definition, phonetic pronunciation, part of speech, a real-world example, etymological roots, historical context, and a concise memory hint. Tap any term to see its full detail card. Star the ones you want to revisit later.

The built-in search bar lets you find any term instantly. You can also browse alphabetically or filter by topic — tap a category tab at the top to narrow the list to just the branch of biology you are studying.

WHAT EACH ENTRY INCLUDES

• Definition — a precise, exam-ready explanation of the term
• Pronunciation — phonetic guide so you can say it correctly
• Example — a sentence placing the term in real-world context
• Etymology — the Greek, Latin, or other roots behind the word
• First Described — who coined or discovered the concept and when
• Hint — a short memory aid to help the term stick
• Related Terms — links to connected concepts in the lexicon

11 BIOLOGY TOPICS

• Anatomy — body systems, organs, tissues, skeletal and muscular structure
• Biochemistry — enzymes, metabolic pathways, macromolecules, ATP
• Cell Biology — organelles, membrane transport, mitosis, meiosis, cell signalling
• Ecology — food webs, ecosystems, population dynamics, biodiversity
• Evolution — natural selection, speciation, phylogenetics, evidence for evolution
• Genetics — inheritance, DNA replication, gene expression, mutations
• Immunology — innate and adaptive immunity, antibodies, vaccination
• Microbiology — bacteria, viruses, fungi, protists, antibiotic resistance
• Molecular Biology — DNA technology, PCR, CRISPR, recombinant DNA
• Physiology — homeostasis, endocrine signalling, nervous coordination
• Plant Biology — photosynthesis, transpiration, plant hormones, reproduction

TEST YOURSELF

Switch to Quiz mode and choose a topic. Each quiz presents 20 true-or-false statements drawn from the lexicon. Answer correctly to build your streak. Get one wrong and you will see a detailed explanation of the correct answer — every mistake becomes a learning moment.

If you want another chance, watch a short reward video to continue where you left off (up to 2 continues per round). Your best streak for each topic is saved so you can track your progress over time.

DESIGNED FOR COMFORTABLE STUDYING

Bio Lexicon supports both light and dark mode, adapting to your system appearance automatically. The interface is native on iPhone and iPad, with a layout that makes it easy to scan entries quickly or read them in full.

FREE TO DOWNLOAD

Bio Lexicon is completely free. The app is supported by ads, with optional reward videos during quizzes.