Its spectral type is A1p; the "p" stands for peculiar, as its spectrum is characteristic of an α2 Canum Venaticorum variable.

It has long been suspected that Epsilon Ursae Majoris is a spectroscopic binary, possibly with more than one companion.

[12] A more recent study suggests Epsilon Ursae Majoris's 5.1-day variation may be due to a substellar object of about 14.7 Jupiter masses in an eccentric orbit (e=0.5) with an average separation of 0.055 astronomical units.

The traditional name Alioth comes from the Arabic alyat al-hamal ("the sheep's fat tail").

[19] The United States Navy's Crater class cargo ship USS Allioth (AK-109) was named after the star.