Main Entry: mi·cro·tu·bule

Pronunciation: \ˌmī-krō-ˈt(y)ü-(ˌ)byü(ə)l\

Function: noun

: any of the minute tubules in eukaryotic cytoplasm that are composed of the protein tubulin and form an important component of the cytoskeleton, mitotic spindle, cilia, and flagella

[microtubule illustration]

—mi·cro·tu·bu·lar \-byə-lər\ adjective