focus
focus Lexical Profile
focus Game Scores & Validity
• noun
The center of interest, attention, or activity.
"The main focus of the conference was sustainable urban development."
The state or quality of having or producing clear visual definition.
"She turned the camera ring until the distant mountains came into sharp focus."
Close mental concentration or undivided attention directed toward a specific task or goal.
"Maintaining focus during a three-hour examination requires discipline and rest."
A point at which rays of light, heat, or sound meet after being reflected or refracted, or a fixed reference point used to define a geometric curve such as an ellipse or parabola.
"A parabolic mirror directs parallel rays of light toward a single focus."
The exact underground point of origin of an earthquake, or the localized site of a pathological infection within the body.
"Seismologists determined that the focus of the tremor lay thirty kilometers beneath the ocean floor."
• verb
To direct one's attention, effort, or mental concentration toward a particular subject, task, or goal.
"The research team decided to focus on renewable energy storage solutions."
To adjust an optical instrument or the eye so that an image becomes clear and sharply defined.
"It took a moment for her eyes to focus in the dimly lit theater."
To cause rays of light, sound, or energy to converge at a single point.
"A convex lens can focus sunlight onto a tiny spot."
Word Nuance & Usage
As a noun, both 'focuses' and 'foci' are accepted plurals, with 'foci' preferred in scientific, mathematical, and technical contexts. As a verb, both single-s ('focused', 'focusing') and double-s ('focussed', 'focussing') spellings occur, though the single-s form is standard in American English and increasingly preferred in British English.
• Rhymes for focus
Word Origin & Etymology
Borrowed in the 17th century directly from Latin 'focus', meaning 'hearth' or 'fireplace' (the domestic center of a Roman home). The astronomer Johannes Kepler first introduced the word in a scientific sense in 1604 to describe the burning point of a lens where light rays converge.