%musth%

a. [ Hind. mast intoxicated, ruttish, fr. Skr. matta, p.p. of mad to rejoice, intoxicate. ] (Zool.) Being in a condition of dangerous frenzy, usually connected with sexual excitement; -- said of adult male elephants which become so at irregular intervals, typicaly due to increased testosterone levels. -- n. (a) The condition of frenzy. (b) An elephant in must. [ Webster 1913 Suppl. +PJC ]