It doesn’t mean “Traditionalist”. “Traditionalist” means Traditionalist, as in “somebody who loves the the forms of piety associated with the Latin rite, particularly as they were lived before the Second Vatican Council”. One can be a Traditionalist without being a Reactionary and lots of people are: very lovely and wonderful people with a real joie de vivre, a sense of humor, typically large and happy families, and a generosity of spirit that is fetching and attractive. Those sorts of folk typically love the Church. The prefer the Tridentine liturgy but love and appreciate those members of the Church who worship in other rites or the Ordinary Form. The live by the maxim, “In essential things, unity; in doubtful thing, liberty; in all things charity.”
A Reactionary is somebody who often *uses* Traditionalism as a sort of excuse for, well, reaction. Their principal approach to life is to see the vast majority of the human race, including most Catholics, as enemies of a Church that exists in their imagination and in the past, but not in real life (except in their living room and among a small circle of the faithful online). Their language is dominated by fear, anger, and contempt for almost the entirety of the actual Church as it really exists. They loathe the Council. They loathe the conciliar and post-conciliar popes (except Benedict who gets a pass because of the Motu Proprio, but whose encyclicals are ignored and who is treated as a coward for resigning and handing the papacy over to the accursed Francis). Jews figure largely as hobgoblins in the Reactionary mind. Protestants are beneath contempt. Most of their fellow Catholics are Kumbayah Catholic wusses who prattle about love and mercy when what is necessary always and at all times is the fury of Jesus against the moneychangers, exposure and denunciation of evil, and perpetual focus on the Trinity of Abortion, Contraception and Homosexuality. Mercy is weakness. Law is salvation. The bulk of the human race is a mass damnata. Only perfect Tridentine liturgy can save us. Talk of “personal relationship with Jesus” is Protestant subjectivism.