This is the 1392nd most frequent Arabic word.
بعضهم
"Some of them."
Here, 'بعضهم' refers to mutual visitation among members of a group.
زار العرب بعضهم بعضاً في العيد.
The Arabs visited each other during the holiday.
In this sentence, 'بعضهم' specifies a subset of a defined group.
بعضهم كان يلعب في الحديقة بينما الآخرون كانوا يتحدثون.
Some of them were playing in the garden while others were talking.
'بعضهم' denotes individuals within a group who participated in a discussion.