Sentence:  She fell asleep leaning on her hand , hearing the house creaking as though it were a living a private life of its own these two hundred years , hearing the birds rustling in their cages and the occasional whirring of wings as one of them landed on the table and walked across the newspaper to perch in the crook of her <WSD>arm</WSD> . 
Meaning of the word marked with <WSD> tags:  a human limb; technically the part of the superior limb between the shoulder and the elbow but commonly used to refer to the whole superior limb