10 most difficult English words:
1. Abjure : formally reject or disavow a formerly held belief
2. Camaraderie : the quality of affording easy familiarity and sociability
3. Defunct : no longer in force or use; inactive
4. Ephemeral : anything short - lived, as an insect that lives only for a day
5. Incumbent : necessary as a duty or responsibility; morally binding
6. Instigate : provoke or stir up
7. Munificent : very generous
8. Rife : excessively abundant
9. Trite : repeated too often; over - familiar through overuse
10. Ubiquitous : being present everywhere at once