unretentive

/ˌʌnrɪˈtɛntɪv/
adjective
  1. Not able to remember or hold information well; having a poor memory.
    • His unretentive mind made studying for exams a real challenge.
    • She is unretentive when it comes to names, often forgetting them moments after an introduction.
    • The teacher noticed that the student was unretentive with new vocabulary words and needed extra review.
  2. Not able to hold or keep something physically, such as liquid or heat.
    • The sponge became unretentive after years of use and no longer absorbed spills.
    • The unretentive soil drained water so quickly that the plants wilted.
    • This old thermos is unretentive and can't keep coffee hot for more than an hour.
Antonyms
What does "unretentive" mean? | whatsthatwordmean | whatsthatwordmean