Background: Fibronectin harbors a cryptic antiadhesive site that is able to inactivate ␤-1 integrins. Results: Spontaneous anoikis of nontransformed fibroblasts was caused by exposure of this antiadhesive site and its recognition by membrane-resident eEF1A. Conclusion: eEF1A functions as a membrane receptor triggering cell detachment, resulting in anoikis.Significance: The results demonstrate a new function of eEF1A that contributes to cell regulation, including anoikis.