We don't have synonyms for destrier yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are destroyer, deserter and desirer.
(n) :
a large warhorse, especially of a medieval knight
"1819, I am resolved to share or avert the danger; which, that I may the better do, I would crave of thee the use of some palfrey whose pace may be softer than that of my destrier." -- Walter Scott, Ivanhoe"
(n) :
a large warhorse, especially of a medieval knight
"1819, I am resolved to share or avert the danger; which, that I may the better do, I would crave of thee the use of some palfrey whose pace may be softer than that of my destrier." -- Walter Scott, Ivanhoe"