noun, plural: tissues
An aggregate of cells in an organism that have similar structure and function
A tissue is an aggregate of cells that having the same structure and function. The fundamental types of tissues in animals are as follows:
In plants, the different types of tissues are the embryonic or meristematic tissues (such as apical meristem and cambium), the permanent tissues (e.g. epidermis, cork, trichome), and the reproductive tissues (i.e. sporogenous tissues). The permanent tissues may be further classified into fundamental (e.g. parenchyma, collenchyma, sclerenchyma) and complex (e.g. phloem and xylem tissues).
Tissues that work in unison to carry out a specific set of functions form an organ.
Word origin: Middle English tissu, a rich kind of cloth, from Old French, from past participle of tistre, to weave, from Latin texere