A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton—proton collisions at √s = 13 TeV. The data sam- ple was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9 fb−1. The measurement is performed for the νjj final state (with ν indicating a lepton—neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass mjj > 120 GeV and transverse momenta pTj > 25 GeV. The cross section of the process is measured in the electron and muon channels yielding σEW (Wjj) = 6.23 ± 0.12 (stat) ± 0.61 (syst) pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anoma- lous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are −2.3 < cWWW /Λ2 < 2.5 TeV −2, −8.8 < cW /Λ2 < 16 TeV−2, and −45 < cB/Λ2 < 46 TeV−2. These results are combined with the CMS EW Zjj analysis, yielding the constraint on the cWWW coupling: −1.8 < cWWW /Λ2 < 2.0 TeV −2