This is the 9785th most frequent Japanese word.
街灯
Streetlight.
Here, "街灯" refers to streetlights in general, emphasizing their function of illuminating streets during nighttime.
街灯は夜道を明るくします。
Streetlights brighten the paths at night.
"街灯" is used to highlight the aesthetic aspect of streetlights contributing to the ambiance of the environment.
古い街灯が街の雰囲気を演出している。
The old streetlights create an atmosphere for the town.
In this case, "街灯" is specifically referring to a singular streetlight within the context of a park.