means a soft, thin piece of absorbent paper used for blowing your nose, wiping away tears, or general cleanup, then thrown away — or, in biology, a group of similar cells forming part of an organism.

from From the Old French 'tissu,' meaning a woven or rich fabric, the past participle of 'tistre,' 'to weave,' which traces back to Latin 'texere,' 'to weave' — the same loom that gave us 'textile' and 'text.' Originally 'tissue' meant fine woven cloth, then any interlaced web (a 'tissue of lies' keeps that thread alive); only later did it settle onto thin, gauzy paper and the woven-together cells of living bodies.