keen eyes; piercing gaze; penetrating eyes
Describes sharp, discerning eyes that seem to see through things. Often used in literary or formal contexts.
insightfulness; acumen
Refers to mental sharpness and the ability to grasp the essence of things. Often used in phrases like 炯眼な判断 (keen judgment).
His keen eyes miss no detail.
The detective has a piercing gaze and finds even the smallest clues.
Her insightful analysis solved the problem.
鋭い (するどい) is a common adjective meaning 'sharp' (for blades, senses, or minds). 炯眼 is a more literary, noun/adjectival noun form specifically for eyes or insight.
Standard kanji spelling; the character 炯 means 'bright' or 'clear'.
Variant form using 烱, a less common character for the same meaning.
From Chinese 炯眼 (jiǒngyǎn), literally 'bright eyes'. The character 炯 means 'bright, shining', and 眼 means 'eye'. The word entered Japanese as a literary term for sharp perception.