Pointer
来自Big Physics
wiktionary
point + -er
etymonline
pointer (n.)
mid-14c., "a tiler" (early 13c. as a surname), agent noun from point (v.). From c. 1500 as "maker of needlepoint lace." From 1570s as "thing that points;" meaning "dog that stands rigid in the presence of game, facing the quarry" is recorded from 1717. Meaning "item of advice" is recorded by 1883.
