retentive

To be retentive means having a strong ability to remember information, details, or what you have learned over time. It usually describes a person, mind, or memory that holds onto facts and experiences well. For example: "She had a retentive memory and could recall facts from lectures months later," or "He was a retentive learner who rarely forgot a new word once he had studied it."

The word is mostly used in connection with memory, learning, and recall. Someone with a retentive memory may remember names, dates, instructions, stories, or fine details that other people forget. Because of that, it often has a positive sense when speaking about study, teaching, research, or any work where careful remembering matters.

In some contexts, especially older or more formal ones, it can also mean simply "tending to hold on" to something. That broader sense is much less common in everyday English, so most learners should think of retentive mainly as a word about memory rather than emotion or attitude.

Historically, the word comes from the Latin retinere, meaning "to hold back" or "to keep." That root explains why the word has the idea of holding onto something instead of letting it slip away.

So in normal use, if you call someone retentive, you are usually saying that they remember things well and keep what they learn.