粗大|そだいsodai[0]heiban (flat)

1. na-adjective, nouncoarse; rough; bulky

• Related粗いあらいNeutralCoarse grains or mesh, rough workmanship; the most everyday word for this. 「粗大」 stresses coarse-and-large bulk and can also mean rough or approximate.
• Related荒いあらいNeutralRough or violent in manner — 「波が荒い」, 「金遣いが荒い」. 「粗大」 describes physical bulk or rough approximation instead.
• Related粗雑そざつWrittenWritten/formal: careless, sloppy work. 「粗大」 can also mean rough or approximate, but its focus is large physical size.
• Related粗末そまつNeutralPoor quality or shabby, and also careless treatment as in 「粗末にする」. 「粗大」 says nothing about quality.
• Related荒っぽいあらっぽいCasualColloquial for violent behavior or rough, slapdash work. 「粗大」 is more written, focused on coarse bulk or rough approximation.
• Related無骨ぶこつWrittenWritten: unrefined manners or a rugged look, as in 「無骨な手」. 「粗大」 stresses coarse-and-large size.
• RelatedごついCasualColloquial: big, solid and hard, as of hands or features. 「粗大」 is the more written word.
• Related粗笨そほんWrittenWritten word for crude, clumsy workmanship; rarely used. 「粗大」 stresses coarse-and-large bulk.
• Antonym微小びしょうWrittenWritten word for extremely tiny; the direct opposite of 「粗大」's coarse bulk.
• Antonym細小さいしょうWrittenFine and tiny; a rare, written opposite of 「粗大」.

Use 「粗大」 for things both coarse and large, as in 「粗大な粒子」 or 「粗大ごみ」, and for rough, approximate handling. For coarse grains, mesh or workmanship use 「粗い」; for violence or wildness 「荒い」; for poor quality 「粗末」. ごつい is colloquial for big and solid; 粗雑 and 粗笨 are written words for sloppy work; 微小 and 細小 are the opposites.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 粗あらく、大おおきなこと。
2. 大雑把おおざっぱなこと。