abstruse

The story

1. Proto-Indo-European · derived from*trewd-“to push; to thrust”
2. Latin · learned borrowing fromabstrūsus“concealed, hidden; having been concealed”
3. English todayabstruse

PIE word *h₂epó Learned borrowing from Latin abstrūsus (“concealed, hidden; having been concealed”), an adjective use of the perfect passive participle of abstrūdō (“to conceal, hide; to push or thrust away”), from abs- (from ab- (prefix meaning ‘away; from; away from’)) + trūdō (“to push, shove; to thrust”) (ultimately from Proto-Indo-European *trewd- (“to push; to thrust”)). Cognates * Catalan abstrús * German abstrus (“abstruse”) * Italian astruso (“abstruse”) * Middle French abstruse (modern French abstrus, abstruse (“(derogatory, literary) abstruse”) * Portuguese abstruso (“abstruse”) * Spanish abstruso (“abstruse”)

Words from the same roots

First known use, by meaning

• from mid 16th c. Difficult to comprehend or understand; obscure.
• late 16th – mid 18th c. Concealed or hidden; secret.