meaning: spirit, soul
幽霊 == yuurei == (noun) ghost, specter, apparition, phantom
Top radical is 'rain' (雨), which here
is used for the idea of rain descending from the sky. Bottom
radical is a Non-General Use character meaning 'sorceress/shamaness/temple maiden'. This character
originally referred to a priestess possessed by the spirit of a god which had descended from Heaven.
suggests taking the bottom element as a variant of 'line up' (並), and as a mnemonic:
'Spirits line up in rain -- hardy souls.'