無實體的,不堅固的,薄弱的
Unsubstantial \Un`sub*stan"tial\, a. Lacking in matter or substance; visionary; chimerical.
unsubstantial adj : lacking material form or substance; unreal; "as insubstantial as a dream"; "an insubstantial mirage on the horizon" [syn: {insubstantial}, {unreal}] [ant: {substantial}]