An Etymological Dictionary of Astronomy and Astrophysics

Greater in size, extent, or importance.

Etymology (EN): M.E. majour, from O.Fr., from
L. major, irregular comparative of magnus “large, great,” cognate with Pers. meh “large, great,” as below.

Etymology (PE): Mehin comparative and superlative of
meh “great, large”
(Mid.Pers. meh, mas; Av. maz-, masan-, mazant- “great, important,” mazan- “greatness, majesty,” mazišta- “greatest;” cf. Skt. mah-, mahant-; Gk. megas; PIE *meg- “great”) + -in superlative suffix.