off-the-shoulder       
adjective [ before noun ] uk/ˌɒf.ðəˈʃəʊl.dər/ us/ˌɑːf.ðəˈʃoʊl.dɚ/
 (衣服)无肩的
An off-the-shoulder piece of clothing does not cover the shoulders.
  She wore an off-the-shoulder white top with jeans. 她穿一件白色无肩上衣和牛仔裤。 
 an off-the-shoulder dress/gown 无肩裙子/袍子