復數(shù)：sightings

n.the act of observing

"several sightings of enemy troops were reported"

Sighting instrument
A Crosswire Sighting Tube for Point Quadrat Analysis
Inferring Extinction from Sighting Data
Inferring extinction from a sighting record
A Sighting Technique Using Cameras to Estimate Population Size of Black Bears
Geopolitics and visuality: Sighting the Darfur conflict ☆
Using Public Sighting Information to Investigate Coyote Use of Urban Habitat
The Use of Sighting Records to Infer Species Extinctions: An Evaluation of Different Methods
Estimating Closed Population Size and Number of Marked Animals from Sighting Data
SEASONAL SURVIVAL OF GREATER SNOW GEESE AND EFFECT OF HUNTING UNDER DEPENDENCE IN SIGHTING PROBABILITY