ETYMOLOGY
rom Latin tristitia (sadness) + -ate
EXAMPLE
“…What man is it which lives so happily, which feares not something that would sadden his soule if it fell? Nor is there any whom calamity doth so much tristitiate, as that hee never sees the flashes of some warming joy. Beasts with beasts are terrified and delighted…”
From: Resolves or, Excogitations: A Second Centurie
By Owen Felltham, 1628
Lexicophilia 