乳香脂（Mastic）又称乳香树脂、熏陆香，是从乳香黄连木提取的树脂。它在希腊也被称为「希俄斯之泪」，名字源自传统产地希俄斯。

虽然乳香黄连木在地中海多个地区生长，可是仅有希俄斯南部的乳香黄连木在割开树皮时流出乳香脂。岛上的乳香脂生产由多个自中世纪延续至今的「乳香脂村」组成的合作社控制。

乳香脂本来是液体状，晒干后变成硬而脆的半透明状树脂。咀嚼时，味道初时是苦，经咀嚼后渗出一种可使人提神的轻微的松或香柏味。

乳香脂是制造土耳其软糖的调味料之一。

Chios Mastic Mastiha (Greek:Μαστίχα) is a resin obtained from the mastic tree (Pistacia lentiscus). In pharmacies and nature shops, it is called "Arabic gum" (not to be confused with gum arabic) and "Yemen gum". In Greece, it is known as the "tears of Chios," being traditionally produced on that Greek island, and, like other natural resins, is produced in "tears" or droplets.