  Motivated by the detection of a significant dipole structure in the arrival
directions of ultrahigh-energy cosmic rays above 8 EeV reported by the Pierre
Auger Observatory (Auger), we search for a large-scale anisotropy using data
collected with the surface detector array of the Telescope Array Experiment
(TA). With 11 years of TA data, a dipole structure in a projection of the right
ascension is fitted with an amplitude of 3.3+- 1.9% and a phase of 131 +- 33
degrees. The corresponding 99% confidence-level upper limit on the amplitude is
7.3%. At the current level of statistics, the fitted result is compatible with
both an isotropic distribution and the dipole structure reported by Auger.
