How to say "sole" in Japanese

• 底そこJLPT N3approx.Common
  nounThe physical sense: the bottom of something, such as the sole of a shoe or foot — the surface that touches the ground. The other words all cover the abstract 'only' or 'single' senses instead.
  靴くつの底そこがすり減へってしまった。↗

  The soles of my shoes are worn.
• 唯一ゆいいつJLPT N3approx.Common
  no-adjective, adverbThe sole person or thing: the only one there is, as in the sole heir, survivor, or purpose. It stresses that nothing and nobody else qualifies.
  初はじめの一いち歩ほが唯一ゆいいつの難関なんかん。↗

  The first step is the hardest.
• 単独たんどくJLPT N1approx.Common
  no-adjective, na-adjectiveSole in the sense of single or solo: one person or party acting alone, without companions or partners. It is closer to 'single-handed' or 'solo' than to 'the only one'.
  不幸ふこうは決けっして単独たんどくでは来こない。↗

  Misfortunes seldom come singly.
• 単一たんいつJLPT N1approx.Common
  na-adjective, no-adjectiveReally 'single' or 'unitary': one single kind or undivided whole. As a rendering of 'sole' it is marginal; choose it only when the emphasis is on being one single entity rather than the only one.
  ねじ、てこ、くさび、滑車かっしゃなどは単一たんいつ機械きかいと呼よばれる。↗

  The screw, the lever, the wedge, the pulley, etc. are called simple machines.

Choose 底 for the physical sole of a shoe or foot, 唯一 for the sole (only) person or thing, 単独 for single-handed or solo action, and 単一 for single or unitary senses where 'sole' is marginal.

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

• 底そこbottom
• 唯一ゆいいつonly
• 単独たんどくsole
• 単一たんいつsingle
• ソールsole (of a shoe, golf club, etc.)
• くつぞこsole (of a shoe)
• したびらめsole (any fish of the families Cynoglossidae and Soleidae)
• 足蹠そくせきsole (of the foot)
• 靴裏くつうらsole (of a shoe)
• ただ一つただひとつsole
• オンリーワンonly one (person, thing)
• 底革そこがわsole leather
• ユニuni-
• せめてものminimum
• うしのしたsole (any fish of the families Cynoglossidae and Soleidae)
• せめてもminimum
• 天てんsole (of a Japanese sandal)