shameful

adjective

1. causing shame: shameful behavior.
2. disgraceful or scandalous: shameful treatment.

adjective

1. causing or deserving shame; scandalous

adj.Old English scamful “modest;” see shame (n.) + -ful. Meaning “disgraceful, causing shame” is from c.1300. Related: Shamefully; shamefulness. Middle English shamely (adv.) “shamefully” for some reason has fallen from use. Old English scamlic (adj.) “shameful, disgraceful,” but this also could mean “modest.”