Tenuous; thin; extremely fine; rare; rarefied: as, subtile vapor; subtile odors or effluvia; a subtile powder; a subtile medium. Also subtle.Delicately constituted, made, or formed; delicately constructed; thin; slender; fine; delicate; refined; dainty. Also subtle.Sharp; penetrating; piercing.Same as subtle, 3.Same as subtle, 4.Same as subtle, 5.Same as subtle, 7.To contrive or practise cunningly.To scheme or plan cunningly.To tamper; meddle.