A meticulously curated, AI-enriched dataset of 1,000 high-frequency academic words essential for the TOEFL iBT, IELTS, and advanced English comprehension.
Most open-source vocabulary lists only provide a word and a simple definition. This dataset is engineered for deep linguistic understanding and NLP applications. Each entry includes:
- Academic Theme: The specific field (e.g., Biology, Sociology, Geology) where the word frequently appears.
- Exact Synonyms: Hand-picked synonyms curated specifically for academic reading comprehension.
- Contextual Example: A high-quality, TOEFL-level sentence demonstrating real-world academic usage.
- Difficulty Level: Rated from 3 (Intermediate) to 5 (Advanced).
- POS & Definitions: Precise Part of Speech tagging and accurate English definitions.
toefl_essential_vocabulary.json: Full structured data (Best for Web & Mobile Apps).toefl_essential_vocabulary.csv: Tabular data (Best for Pandas, Data Science, and Kaggle).toefl_essential_vocabulary.txt: Plain word list (Best for quick array imports).
{
"word": "proliferation",
"pos": "noun",
"difficulty": 5,
"theme": "Biology",
"synonyms": ["multiplication", "expansion"],
"definition_en": "Rapid increase in numbers.",
"example_sentence": "The proliferation of invasive plant species severely threatens the delicate balance of the local ecosystem."
}🚀 Get the Full Version & Multilingual App This repository contains the core 1,000-word dataset.
If you are a student preparing for exams, you can access the Full 1,650-Word Database, featuring interactive flashcards, multiple academic sentences for each word, and complete translations in Turkish, German, and Spanish at:
⚖️ License & Attribution This dataset is completely free and open-source under the MIT License. You can use it in your apps, research, or LLM training pipelines.
Attribution Requirement: If you use this dataset in a public repository, website, or research paper, you must provide a clickable do-follow backlink to https://wordlevel.net as the original source of the data.