Q: I recently read Consequences by Penelope Lively and came across the words “diffident” and “feckless.” I memorized them for the College Board exams (in the ’60s), but I go to the dictionary now when I come across them, usually in more “literary” writing. I’ve never heard anyone actually say either word. Have you?

A: “Diffident” and “feckless” don’t often come up in conversation—at least not in ours! These are words we encounter mostly in literary works like the novel you just read.

We do see them once in a while in less literary writing. Diplomats, for example, seem to like using “diffident” and “feckless” to say undiplomatic things.

A US cable revealed recently by WikiLeaks described Philippine President Benigno Aquino as “a diffident, unassertive man.” And another cable referred to Italian Prime Minister Silvio Berlusconi “feckless, vain, and ineffective.”

Today “diffident” means timid, shy, and lacking self-confidence. But this wasn’t always so.

When it first entered English, in the late 1500s, the adjective “diffident” meant distrustful. It came from the Latin diffīdentem, which is traceable to the verb diffīdere (to mistrust) and ultimately to fidere (to trust).

The adjective was preceded by the noun “diffidence,” which was known since before 1400, according to the Chambers Dictionary of Etymology.

In the 17th century, both “diffident” and “diffidence” shifted gears, according to entries in the Oxford English Dictionary. They began to be associated with a lack of confidence in oneself, rather than a lack of confidence in others.

As your ear will probably tell you, the Latin words fides (trust, belief) and fidere have given us a whole family of English words: “confide” and “confidence,” “defy,” “faith,” “fealty,” “fidelity,” “fiduciary,” “perfidy,” and “infidel.” And believe it or not, “federal” is part of the family!

“Feckless,” on the other hand, comes not from Latin (at least not directly) but from dialects spoken in Scotland and northern England. It was first recorded in the late 1500s and means—listen for the echo—ineffective.

We know what you’re thinking. Is there a word “feck,” to which “less” was added? The answer is yes!

“Feck” is in fact a Scottish shortening of “effect,” Chambers says. And the ancestor of “effect” is the Latin verb efficere, meaning to work out or bring about. The Latin word is a compound of ex (out) and facere (to make or do).

The noun “feck” was first recorded in the late 1400s and means, in the words of the OED, “operative value, efficacy, efficiency” and hence also “vigour, energy.” It’s still used in parts of Britain today.

Originally, the OED says, “feckless” was used to describe things (not people) that were considered “valueless, futile, feeble.”

Later, it was used chiefly to describe people believed to be “lacking vigour, energy, or capacity; weak, helpless; (now more usually) irresponsible, shiftless.”

So “feckless,” too, has shifted gears somewhat. These days, it often describes not just incapacity or inability but moral weakness.

They’re both fine old words—“diffident” and “feckless.” It’s nice to come across them in literary writing as well as in leaked diplomatic cables.

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