Vindictive vs. Vindicative

Solution 1:

The two terms appears to have a common origin, but "vindictive" has retained its original negative meaning while "vindicative" has also developed a more positive connotation:

From Grammarphobia:.

• The verb vindicate comes from the Latin vindicare, meaning to claim, set free, punish, or avenge. In the 16th and 17th centuries, the English word reflected both the negative and positive sides of its Latin heritage.

• First, it meant to avenge or exercise vengeance. Later it came to mean punish; rescue or set free; justify or clear (as from suspicion or dishonor); establish possession of something; and make good or defend against encroachment.

Origin of vindictive:

• The adjective “vindictive” (from the Latin vindicta, meaning revenge), was preceded by an earlier form, “vindicative,” in the 1500s, and has had a generally grim history since entering English.

• When “vindictive” first showed up in the early 1600s, it described someone “given to revenge; having a revengeful disposition,” according to the Oxford English Dictionary. In other words, someone who liked punishing people or holding a grudge.

• In former days, “vindictive” was also used to describe anything punitive, retributive, or avenging. Today we use the legal phrase “punitive damages,” but the OED cites a quotation from 1813 about “vindictive damages.”

Both terms appear to derive from "vindication",

• The Chambers Dictionary of Etymology suggests that “vindicate” could be a back-formation from an earlier word, “vindication,” which first appeared in English in the late 1400s and originally meant the act of avenging. (A back formation is a word formed by dropping a real or imagined part from another word.)

• The OED says that “vindication” made its first published appearance in William Caxton’s printing of Aesop’s Fables (1484): “An asse … smote hym [the lion] in the forhede with his feete by maner of vyndycacion.”

but through the centuries developed different nuances:

• So both “vindicate” and “vindictive” come from notions of vengeance and punishment. Although “vindictive” has continued to embrace the dark side, “vindicate” has lightened up.