How to say "focus" in Japanese

• フォーカスCommon
  nounThe loanword for the focus of a camera, microscope, or similar instrument — the sharpness of the image and its adjustment. Photography and microscopy are its typical contexts; ピント covers much the same ground.
• 焦点しょうてんJLPT N2approx.Common
  nounThe word for 'focus' as a point or abstract center: the focal point of a lens, and figuratively the point where attention, discussion, or a problem converges, as in 'the focus of a debate'.
  顕微鏡けんびきょうの焦点しょうてんを合あわせなさい。↗

  Adjust the microscope's focus.
• ピントCommon
  nounThe focus of a lens — the point where light converges to give a sharp image. Whether a photo counts as in or out of focus is a matter of its ピント.
  ピントがズレている。↗

  That's a little out of focus.
• 震源しんげんCommon
  nounStrictly the seismological sense: the point underground where an earthquake originates — the hypocenter, called the focus in technical English. Seldom the word you want for cameras, lenses, or attention.
• 病巣びょうそうCommon
  no-adjectiveA medical term: a localized site of disease in the body — a lesion or nidus, 'focus' in medical English. For everyday or figurative 'focus' it is not the word you want.

「フォーカス」 and 「ピント」 both cover camera and lens focus; 焦点 is the word for focal points in optics and for the figurative focus of attention; 震源 and 病巣 are strictly the earthquake and medical senses.

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

• フォーカスfocus (of a camera, microscope, etc.)
• 焦点しょうてんfocus
• ピントfocus (of a lens)
• 震源しんげんhypocentre (of an earthquake)
• 病巣びょうそうfocus
• 主眼しゅがんmain purpose
• 中心ちゅうしんcenter
• 注ぎ込むつぎこむto invest in
• 焦点を当てるしょうてんをあてるto focus (on)
• 焦点を合わせるしょうてんをあわせるto focus (a camera, telescope, etc. on something)
• とりとめcoherence
• 的を絞るまとをしぼるto narrow in (on)
• ベクトルdirection (e.g. of one's activities or interests)
• 軸足じくあしemphasis
• 矛先ほこさきfocus (of one's attack, criticism, etc.)
• 的まとobject
• 集中しゅうちゅうconcentration (of population, buildings, power, etc.)
• 本丸ほんまるcore