This is the 263rd most frequent Hindi word.
आकर
The Hindi word "आकर" means "shape" or "form" in English.
In this sentence, "आकर" is a compound indicative of an action performed upon arriving (running here) before the main verb action (sitting).
वह दौड़ते हुए आकर तुरंत बैठ गया।
He came running and immediately sat down.
Here, "आकर" combines "come" and "tell" to signify she informed *after* arriving.
उसने आकर बताया कि समस्या हल हो चुकी है।
She came and informed that the problem was resolved.
In this context, "आकर" demonstrates an action sequence where I finished coming before closing the door.