You go first.

Dear Word Detective: In some recent reading of several different 19th century authors, I’m finding that the term “enthusiast” appears to mean something different in these texts than in our current usage. Several times, it’s applied in description of an individual in a tone that is scathing, contemptuous, and downright nasty. Or, it’s used by a character trying to establish his bona fides by claiming “I’m not an enthusiast by any means,” for example. Can you shed any light on this difference? How did a term that today generally conveys cheerful energy and motivation evolve from one that seems to imply a moral or intellectual weakness? — Chris, Kansas City.

Well, now here’s an appropriate question for me to answer. I just happen to be known as “Mister Enthusiasm” among my friends and family, because I’m always up for tackling a task, embarking on a spontaneous adventure, or just spinning the Great Roulette Wheel of Life first thing every morning. Just kidding. My enthusiasm quotient has been at low ebb since I was twelve, when I discovered Mister Ed couldn’t really talk. A world devoid of talking animals cannot dazzle me with its tawdry pageant, so I take the Homer Simpson approach to life: “Why go out? We’ll just end up back here.”

It would seem that you have a sharp eye (or ear) for overtones. “Enthusiast” and its parent “enthusiasm” have indeed markedly changed their connotations since “enthusiasm” first appeared in English in the early 17th century. The root of “enthusiasm” was the Greek “entheos,” which meant literally “possessed by a god.” (That “theos” is also found in “theology” and related English words.) This produced the Greek words “enthousiasmos” (“divine inspiration”) and “enthousiazein” (“to be inspired or possessed by religious fervor”). “Enthusiast,” “enthusiasm” and “enthusiastic” all arrived in English with these religious overtones.

In the Puritan England of the day, however, high-octane religious fervor was frowned upon, and “enthusiast” took on a definite connotation of disapproval (“One who erroneously believes himself to be the recipient of special divine communications; in wider sense, one who holds extravagant and visionary religious opinions, or is characterized by ill-regulated fervor of religious emotion,” Oxford English Dictionary (OED)) and it was applied to people we would probably call “zealots” or “fanatics” today. John Wesley, one of the founders of Methodism, noted that “It is the believing those to be Miracles which are not, that constitutes an Enthusiast” (1746).

By the mid-18th century, however, the religious sense was fading, and “enthusiast” was being used in a more neutral secular sense to mean someone who was full of “enthusiasm” for a cause, a person, a principle, etc., “enthusiasm” itself having come to mean “passionate eagerness or interest” in something, usually based in a strong belief in its merits (“Bob’s enthusiasm for saving money with DIY roof repairs overcame his fear of heights, but not his balance problems”). This “big fan of” or “eager to get started” sense of “enthusiast” is the positive sense we use today. The OED does note, however, that when any of this family of words are used in a disparaging or sarcastic sense, it’s almost always “enthusiast” (“Since it was a weekend, Bob discovered that the ER was already full of DIY enthusiasts”).

Speaking of the “enthusiast” family, the “troubled teen” of the lot is definitely the verb “to enthuse,” which means either “to make enthusiastic” or “to become enthusiastic.” Labeled “an ignorant back-formation of enthusiasm” by the OED, “enthuse” appeared in the early 19th century and didn’t raise any hackles among usage mavens until 1870. Since then it has been regularly denounced, but also regularly used by such notable writers as Robert Frost, Wilfred Owen, and Julian Huxley, as well as many others who found it useful.