unable to find the way
no longer visible
bewildered or helpless
ruined or destroyed physically or morally
damned
no longer possessed
one's lost youth
no longer known
the lost art of letter-writing
(usu + in) rapt or absorbed
lost in reverie
be lost for words
to be unable to think what to say, e.g. because of shock
be lost on/be lost on somebody
to be unnoticed or unappreciated by somebody
get lost
informal (usu in imperative) to go away