Definitions for virusoidˈvaɪ rəˌsɔɪd
Random House Webster's College Dictionary
a small particle of RNA associated with the larger RNA of some infectious plant viruses.
Ref: Compare viroid.
Origin of virusoid:
the smallest of viruses; a plant virus with its RNA arranged in a circular chromosome without a protein coat
A circular single-stranded RNA, similar but not identical to a viroid, dependent on plant viruses for replication and encapsidation.