“I am the offspring of illicit love.”^1(p814)

“Only suffering… can elicit the perfumes of the soul.”^1(p503)

“Henry had been soliciting the pope for some time, in order to obtain a divorce from Catherine of Aragon, his queen.”^1(p1822)

Illicit, elicit, solicit. The above examples make it abundantly clear that these words have distinctly different denotations; yet they are often confused or misused, even by careful writers. In medical contexts, it is especially important to preserve the distinctions between them.

Illicit, denoting simply “not permitted; unlawful”^2(p618) (and sometimes used colloquially to indicate naughty, unseemly, or immoral), has limited use in medical writing. For example, written materials might convey the risks associated with use of illicit drugs, discuss illicit relationships between researchers and industry, or report on the illicit trade in human body parts. Beyond such instances, however, the word does not often come into play.

Elicit, however, is another story. Denoting “to call forth or draw out (as information or a response)” or “to draw forth or bring out (something latent or potential),”^2(p404) the word occurs frequently in medical contexts. It might be used in both senses regarding a patient–physician encounter: for example, a physician evaluating a patient’s pain will ask questions to elicit information about the characteristics of the pain (eg, location, nature, duration, exacerbating factors). From the patient’s perspective, that is the easy part, and patients might well wish this were the end of the matter; however, having thus elicited mere information about the patient’s pain, the physician then embarks on maneuvers expressly designed to elicit the real thing. In written materials covering the basic sciences and their clinical applications, elicit is perhaps most frequently used in the second sense noted above. For example,a writer might report that a new vaccine elicits a given immune response, describe pathological mechanisms that elicit organ damage, or present a theory of how a treatment might elicit changes in gene expression.

Even accomplished writers sometimes confuse the homophones illicit and elicit. However, these terms are easily distinguished from each other: illicit is always an adjective, whereas elicit is—in current usage—always a verb. (It also can help to remember that illicit denotes illegal; for the temperance-minded, the illicit distillation of spirits might also come to mind.)

Troublesome as homophones can be, however, sometimes near-homophones can be more so, especially when they are similar in meaning. For example, elicit and solicit—the latter most frequently used in medical contexts in the sense of “to approach with a request or plea”^2(p1187)—are often used interchangeably, with solicit perhaps more frequently used in place of elicit.³ However, such use obscures an important distinction. The Oxford Dictionary of American Usage and Style perhaps explains this distinction most succinctly: “To solicit a response is to request it. To elicit a response is to get it.”³ Thus, in the patient–physician encounter alluded to above, the physician solicits information regarding the patient’s pain and then performs a physical examination to elicit and evaluate actual pain. The Oxford resource also points out an ambiguity that can arise when elicit and solicit are confused: “‘Sentient representatives expect the core group to solicit [read elicit?] response from about 4,000 people.’”³ In other words, will the group solicit responses from 4000 persons, or will the group approach a larger number of persons to try and elicit 4000 responses, knowing that some persons approached might not reply? In medical contexts, the distinction has obvious implications for reports of survey studies and possibly for discussions of power calculations in reports of clinical trials.

Three quick tips:

* Looking for an adjective to describe something as immoral, forbidden, or illegal? Illicit (think illicit = illegal) might be the ticket.

* Looking for a verb to convey the requesting of information? Consider solicit.

* Looking for a verb to convey the obtaining of information or the drawing forth of a response or change? Consider elicit (think elicit = get).—Phil Sefton, ELS

1. The Compact Oxford English Dictionary. 2nd ed. Oxford, England: Oxford University Press; 1991.

2. Merriam-Webster’s Collegiate Dictionary. 11th ed. Springfield, MA: Merriam-Webster Inc; 2003.

3. Garner BA. The Oxford Dictionary of American Usage and Style. New York, NY: Oxford University Press; 2000:309.