Word Study
subsesqui-
CIDE DICTIONARY
subsesqui-, [Pref. sub- + sesqui\'cf.].
A prefix (also used adjectively) denoting the combination of constituents (especially electro-negative and electro-positive bodies) in the proportion of two to three; as, a subsesqui acetate, i. e. , a salt having two equivalents of acetic acid to three of the base. [1913 Webster]
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