一眼

a glance / a quick look / a glimpse

one / single / a (article) / as soon as / entire; whole; all; throughout / "one" radical in Chinese characters (Kangxi radical 1) / also pr. [yao1] for greater clarity when spelling out numbers digit by digit

eye / small hole / crux (of a matter) / CL:隻|只[zhi1],雙|双[shuang1] / classifier for big hollow things (wells, stoves, pots etc)