The adjective defective means faulty, marked by a defect.

The adjective deficient means inadequate or insufficient, lacking an important element or ingredient.

Examples:

• A spokeswoman said the cause of the disaster was probably a defective lid on one of the turbines.
• The diets of many people in this country are deficient in essential nutrients.

Practice:
(a) "No mind is thoroughly well organized that is _____ in a sense of humor." (Samuel Taylor Coleridge)

(b) "Human kindness is like a _____ tap, the first gush may be impressive but the stream soon dries up." (P.

D. James)
Answers to Practice Exercises

Glossary of Usage: Index of Commonly Confused Words