insubstantial：非实体的，不坚固的

in-,不，非，substantial,结实的，牢固的，实体的。

• odor
• odoriferous
• odorous
• odyssey
• oedema
• Oedipal
• Oedipus
• Oedipus complex
• oeuvre
• of
• of-
• off
• offal
• offbeat
• off-Broadway
• offcut
• off-duty
• offence
• offend
• offense
• offensive
• offer
• offering
• offertory
• offhand