astern 
/əˈstɚn/ adverb
/əˈstɚn/ adverb 1 : in, at, or toward the back of a boat or ship : in, at, or toward the stern
▪ The island lay astern (of us) [=the island was behind us] as we sailed east. 2 of a boat or ship : in a reverse direction
▪ The ship went full speed astern.
▪ The island lay astern (of us) [=the island was behind us] as we sailed east.
▪ The ship went full speed astern.
