This is the 3359th most frequent Arabic word.
عابرة
"عابرة" means "passing" or "transient."
In this sentence, the word "عابرة" is used as an adjective to convey the meaning of something passing or transient, here describing the cloud.
كانت السحابة عابرة في السماء.
The cloud was passing in the sky.
Here, the term "عابرة" is used metaphorically to describe an idea as fleeting or not permanent.
هذه فكرة عابرة خطرت في ذهني.
This is a fleeting thought that came to my mind.
In this context, "عابرة" is part of the phrase "عابرة الطريق," where it describes someone passing by on the street.