- 1[intransitive] founder (on something) (of a plan, etc.) to fail because of a particular problem or difficulty The project foundered after problems with funding. The peace talks foundered on a basic lack of trust.
- 2[intransitive] founder (on something) (of a ship) to fill with water and sink Our boat foundered on a reef.
NAmE//ˈfaʊndər//(formal)Verb Forms present simple I / you / we / they founder
he / she / it founders
past simple foundered
-ing form foundering