noun
A dirty mark or discoloration on a surface, fabric, or object. Often used for stains from food, drink, or dirt.
ワイシャツにコーヒーの染みがついた。
I got a coffee stain on my dress shirt.
この染みは洗っても落ちない。
This stain won't come out even after washing.
noun
skin spot; blemish; freckle
A spot or discoloration on the skin, such as age spots, liver spots, or freckles. Often written in kana or katakana in this sense.
See also: 肝斑
年をとると、顔にシミができやすくなる。
As you get older, skin spots tend to appear on your face.
このクリームはシミに効くらしい。
This cream is said to work on blemishes.
Derived from the verb 染みる (しみる, 'to soak in, to stain'). The noun form refers to the resulting mark left by something that has soaked in.