1. affected by unhappiness or grief; sorrowful or mournful: to feel sad because a close friend has moved away.
2. expressive of or characterized by sorrow: sad looks; a sad song.
3. causing sorrow: a sad disappointment; sad news.
4. (of color) somber, dark, or dull; drab.
5. deplorably bad; sorry: a sad attempt.
6. Obsolete. firm or steadfast.
"people can be sad for people."
"people can be sad in/at/on times."
"people can be sad for countries."
"people can be sad at things."
"people can be sad for friends."
This list can help you learn new vocabulary more quickly and be able explore other words more easily.