Yes.
The first published results of measurements made by O. Flachsbart of the AVA Göttingen on a flat disk can be found in the collection Ergebnisse IV (PDF!). He reported on a hysteresis in the angle of attack range between 39° and 42°, where the wing is either stalled or not, depending from which side this angle of attack range is approached.
Lift and pitching moment coefficients of a flat disk, page 97 of Ergebnisse IV
When C. H. Zimmerman tested disk-shaped wings with an Clark Y airfoil section in the early 1930s in the NACA 7 x 10 ft wind tunnel, he called them circular airfoils. The results of this testing can be found in NACA Technical Note 539 (PDF!) from August 1935.
Figures 10 and 11 from the last page of NACA TN 539
Sighard Hörner collected the little data available on circular wings in his book Fluid Dynamic Drag (page 17-8) and concluded:
Disregarding any dreams of "flying saucers", the athletic implement
called discus seems to be the only practical application of a circular
planform.
However, Zimmerman went on to inspire the Vought V-173, the "flying pancake" of 1942, from which the Vought XF5U was developed.
Vought V-173 in flight (picture source)