endosome

en·do·some

noun \ˈen-də-ˌsōm\

Definition of ENDOSOME

1

: a conspicuous body other than a chromatin granule that occurs within the nuclear membrane of a vesicular protozoan nucleus and is either a karyosome or a nucleolus

2

: a vesicle formed by the invagination and pinching off of the cell membrane during endocytosis