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abyssal abstract abstruse abysmal alto bottomless bowels brighter bright brine brightest broader broadest broad cavernous cerebral cleverest clever concentrated contralto cunning dark darkest darker devout difficult engaged engrossed esoteric fainter faint far out far far foxy fruity groovy heartfelt heartiest hearty immersed impassioned impressive insidious intensive intense intelligent intent intimate learned longest long loud loudest louder low lurid low-pitched metaphysical meaningful middle midst more intelligent more difficult more impressive more meaningful more intensive more philosophic more philosophical more philosophical more concentrated more serious most philosophical most philosophical most philosophic most serious occult obscure obscure ocean overlong over one's head passionate philosophical philosophical/philosophic plangent preoccupied profound profound profound protracted psychical rapt recondite resonant resounding rich richest richer ringing roaring rooted ruminative sea secret serious shrewdest shrewd soulful sound subtle subtle throaty thick thoughtful tricky unbroken unfathomable unfathomable widest wide wily wilier