Sad synonyms vary in intensity and nuance, depending on context. Here are key options:

• Strong synonyms: Miserable, wretched, despondent, distraught, heartbroken, crushed, devastated, brokenhearted.

• Moderate synonyms: Downcast, dejected, blue, gloomy, melancholy, sorrowful, upset, disappointed.

• Weak or informal synonyms: Lame, sorry, low, sad (as in "a sad excuse").

• Poetic or reflective synonyms: Wistful, pensive, reflective, nostalgic, poignant, mournful, soulful.

For adverbs: Sorrowfully, mournfully, regretfully, despondently, sadly.

Use context to choose the best fit—e.g., melancholy for thoughtful sadness, miserable for intense suffering, wistful for gentle longing.