in situ
/ɪnˈsaɪtjuː/adverb & adjective
1- in its original place在原位（的）, 在原处（的）：
as adv. mosaics and frescoes have been left in situ镶嵌画和壁画被留在原处
as adj. a collection of in situ pumping engines.一批原来模样的抽水机。
1.1
- in position就位：
as adv. her guests were all in situ.她的客人们都就坐了。
词源
Latin.