Body deep and compressed, the depth subequal to head length, contained 2.4 to 2.7 times in standard length (for fish 11 to 43 cm standard length); body width contained 1.9 to 2.8 times in the depth. Dorsal head profile steep, the interorbital area distinctly convex; preopercle subangular, finely serrate, serrae at rounded corner slightly enlarged; opercular spines inconspicuous; upper edge of operculum straight; posterior nostrils of adults 2 or 3 times larger than anteriors; maxilla reaches about to vertical at rear edge of eye; midlateral part of lower jaw with 2 to 4 rows of teeth. Gill rakers 9 or 10 on upper limb, 15 to 17 on lower limb, 24 to 27 total. Dorsal fin with XI spines and 16 or 17 rays, the third or fourth spine longest, its length contained 2.2 to 2.8 times in head length, the interspinous membranes not or only slightly incised; anal fin with III spines and 8 rays; pectoral fins thin (not fleshy), with 18 to 20 rays; pectoral fins subequal to pelvic fins, their length contained 1.7 to 2.0 times in head length; caudal fin truncate or slightly emarginate. Lateral-body scales distinctly ctenoid, with auxiliary scales; lateral-line scales 63 to 75; lateral-scale series 128 to 147. Pyloric caeca very numerous.
Colour: Adults usually pale bluish grey, covered with black dots and a few scattered, irregular black spots; broad black submarginal band on caudal fin of some large juveniles; pelvic fins usually black tipped. Juveniles with yellow fins; body of small juveniles (to 12 cm standard length) mainly yellow, the head and front part of body with a wash of bluish grey and
faint dark dots.

Western Pacific, from southern Japan to southern Queensland and east to Fiji and the islands of Micronesia; E. cyanopodus is also known from Taiwan, Hong Kong, Viet Nam, Gulf of Thailand, Indonesia, Philippines, Papua New Guinea, New Caledonia, and Lord Howe Island. The only record from the Indian Ocean (a specimen in the Vienna Museum, NMW 40520, 293 mm standard length, from Western Australia) is dubious; the species was not reported from Western Australia by Allen and Swainston (1988), and there are no specimens from there in the Western Australian Museum.

E. cyanopodus is usually found on isolated coral heads in lagoons or bays, but it is also caught at depths to 150 m on the outer reef area. Myers (1989) wrote that it usually swims out in the open, several metres above the bottom, and Grant (1975) noted that it is readily caught by anglers at night. Reported stomach contents are fishes and calappid crabs.

Attains 120 cm total length.

E. cyanopodus is closely related to E. flavocaeruleus and E. multinotatus of the Indian Ocean. These two allopatric species differ from E. cyanopodus only in colour pattern.