All words I’ve confused at one point or another. Explained poorly.
Abstruse / Obtuse
Hard to understand vs. unlikely to understand.
Blond / Blonde and Brunet / Brunette
Male/gender neutral vs. female. Does this distinction still exist? Corrected by an editor in an article I wrote once.
Canvas / Canvass
Canvas sail vs. canvass the neighborhood for the sale.
Carat / Karat
Diamonds vs. gold.
Centrifugal / Centripetal
Centrifugal force pushes out, centripetal force pulls in. Only confusing when you’re spinning something heavy over your head, which is dangerous anyway so just don’t do that and you’ll be fine.
Compliment / Complement
I compliment your sweater, your sweater complements your eyes.
Discreet / Discrete
Circumspect vs. discontinuous.
Divers / Diverse
Several vs. different. Whatever, English.
Hanged / Hung
Hanged if you tried to kill them, hung otherwise. Aside: is this the only word whose conjugation depends on the intent of the subject?
Heroin / Heroine
Drugs vs. Buffy (which surprisingly was never a plot line).
Innervate / Enervate
Supply nerves to an organ vs. weaken. Note that neither of these means to awaken or enliven. Live and learn. ¯\_(ツ)_/¯
Insure / Ensure
Insure against losses vs. ensure no losses. Wait.
Lightening / Lightning
Make lighter vs. electrocuted by God.
Mucus / Mucous
Snot vs. snotty.
Premise / Premises
The basis of an argument vs. the base of an establishment.
Rein / Reign
Anybody can rein a horse but only the horse king reigns over the horses.
Retch / Wretch
Puking sound vs. the person making the puking sound.
Silicone / Silicon
Rubbery stuff vs. computer chip stuff.
Weary / Wary
Tired vs. untrusting.