certain Mr. Brown ((形式))ブラウンさんという人
lady a of certain age ある年齢の女性；((遠回しに))年配の女性（◆５０から６０歳ぐらい）
A genetic predisposition to keratoconus has been observed, with the disease running in
certain families, and incidences reported of concordance in identical twins.
As conferences became contractually bound to
certain bowl games (a situation known as a tie-in), match-ups that guaranteed a consensus national champion became increasingly rare.
History of American football
certain rate of rotation, the beam passes through one gap on the way out and another on the way back, but at slightly higher or lower rates, the beam strikes a tooth and does not pass through the wheel.
Speed of light
At best, cooking times could be specified as the time it took to say a
certain number of prayers or how long it took to walk around a certain field.