At a recent concert in Milwaukee, John Mayer dedicated a song to his girlfriend, Katy Perry, for helping him get through some tough times. “Mayer also publicly thanked Perry for helping him deal with vocal chord problems that left him unable to sing for about 20 months,” UPI reported.

Farther north, Minnesota is trying to determine why the moose population is declining by tracking many of them. “Researchers also placed a second electronic device in the digestive tracks of about 30 of the collared moose that records the animals’ heartbeat and body temperature,” the St. Cloud Times reported.

The two italicized terms, “vocal chords” and “digestive track,” are both logical, both frequently seen, and both incorrectly spelled (for now).

The parts in your throat that vibrate and allow sound to emerge also allow you (and John Mayer and Katy Perry) to sing. Singing is music. Music comes in “chords,” or collections of notes. So you’d think those parts in your throat should be “vocal chords.”

But those parts are also ropelike structures. Many body parts have fanciful names (Adam’s apple, Achilles tendon) or keep to Greek or Latin (medulla oblongata, phalanges), but some are simply descriptive. In this case, cords that allow vocalization are just that: “vocal cords,” though they’re also known as “vocal folds.” Strictly speaking, a human voice can produce only one tone at a time, so “vocal chord” really doesn’t fit anyway.

That doesn’t stop it from fitting into many people’s writing. In 2007, Ben Zimmer wrote on the Oxford University Press blog that “we find contemporary writers opting for vocal chords instead of vocal cords 49% of the time.”Garner’s Modern American Usage lists “vocal chord” instead of “vocal cord” at Stage 2 of the five-stage Language-Change Index, meaning it’s still a capital offense.

If you use a British English dictionary, though, you may use either “cord” or “chord” without penalty from the Empire.

The same arguments apply to “spinal c(h)ord” and “umbilical c(h)ord, by the way, which get similar (mis)treatment.

Now on to “digestive track.” Food goes in one place, and follows a specific route until it is absorbed or emerges. That sure sounds like a “track.” But the more acceptable spelling is “tract.” Hmm, I hear some of you say, “tract” is used to describe a plot of real estate (a “tract of land”). And others will associate “tract” with a pamphlet espousing a cause, as in a “religious tract.” But “tract” is also a bundle of organs working toward a common goal, as your esophagus, stomach, intestines, etc., do.

Garner’s says “track” is more often misused for “tract” in the real estate sense than it is in the digestive sense. Both misuses are also at Stage 2 of the Language-Change Index.

You might say that the digestive misuse is more alimentary. (You knew that was coming!)

Merrill Perlman managed copy desks across the newsroom at The New York Times, where she worked for 25 years.