a spot or stain, esp. of ink on paper.

a blemish on a person's character or reputation

He had been haunted by a blot on his past.

Archaic . an erasure or obliteration, as in a writing.

to spot, stain, soil, or the like.

to darken; make dim; obscure or eclipse (usually fol. by out )

We watched as the moon blotted out the sun.

to dry with absorbent paper or the like

to blot the wet pane.

to remove with absorbent paper or the like.

to make a blot; spread ink, dye, etc., in a stain

The more slowly I write, the more this pen blots.

to become blotted or stained

This paper blots too easily.

Chemistry . to transfer an array of separated components of a mixture to a chemically treated paper for analysis. Compare gel , gel electrophoresis . ?

blot out,

to make indistinguishable; obliterate

to blot out a name from the record.

to wipe out completely; destroy

Whole cities were blotted out by bombs.