Threadlike means thin, long, and delicate like a thread. The word describes anything that resembles the fine strand you'd use to sew a button or stitch fabric.

Scientists use this word often. A doctor might observe threadlike blood vessels called capillaries under a microscope. A botanist might examine the threadlike roots that spread through soil, each one as thin as sewing thread. Marine biologists describe certain jellyfish tentacles as threadlike because they trail behind like long, wispy threads in the water.

You might see threadlike shapes in everyday life too. When you pull apart string cheese, those thin strands are threadlike. The silk a spider spins is threadlike. Even certain clouds can appear threadlike as they stretch across the sky in thin, delicate wisps.

The word emphasizes both thinness and length. A dot isn't threadlike because it's not long enough. A rope isn't threadlike because it's too thick. But a single fiber pulled from a cotton ball? That's perfectly threadlike: slender, elongated, and delicate, just like thread itself.