1
freckle;lentigo;ephelis
家では赤味がかった髪とそばかすのせいで、母が侮蔑を込めて「にんじん」と名付け、皆にもそう呼ばせています。
At home, because of his reddish hair and freckles, his mother scornfully named him "carrot" and had everybody else call him that.
2
Other forms
蕎麦滓 【そばかす】 (rarely used kanji form)