This is the 7448th most frequent Japanese word.
倍加
"倍加" means "doubling" or "multiplication."
Here, '倍加' is used to signify the doubling or intensification of his efforts leading to success.
彼の努力が成功への倍加となった。
His efforts doubled as the pathway to success.
In this example, '倍加' describes the quantitative doubling of the city's population over time.
市内の人口はここ数年で倍加している。
The population of the city has doubled in recent years.
The term '倍加' here refers to the increase or doubling in the quantity of rain today relative to yesterday.