forgetful
adj.having a poor memory or often losing things. You use this to describe someone who cannot remember where they put their keys or what they were going to say.
adj.characterised by a tendency to lose things or forget information. Often used to describe a person's cognitive state or a specific memory-related error.
“He is very forgetful and always loses his glasses.”
“The forgetful student left his textbook at home and had to borrow one from a classmate.”
“While the software is designed to be intuitive, even the most forgetful users should find the recovery process straightforward if they follow the on-screen prompts.”
From Middle English forgetful, forȝetful (suggested by derivative forgetfulnesse, forȝetfulnesse (“forgetfulness”)), equivalent to forget + -ful.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.