Stranger (5)
'stranger' is the definition.
(synonyms)
This is all the clue.
(Other definitions for alien that I've seen before include "Foreigner, outsider" , "extraneous" , "24a [ESTRANGE]" , "coming from overseas" , "Unfamiliar; foreign" .)
'stranger' is the definition.
(more odd)
This is all the clue.
(Other definitions for odder that I've seen before include "More peculiar" , "More unusual" , "more rum" , "More strange or less even" , "Stranger" .)
'stranger' is the definition.
(eerie means odd or strange)
This is the entire clue.
(Other definitions for eerier that I've seen before include "More strangely frightening" , "Weirder" , "More uncanny" , "More spooky" , "Stranger" .)