Webster's Revised Unabridged Dictionary · 1913

Sesquiduplicate

Sesquiduplicate , adjective

[Sesqui- + duplicate.]

Twice and a half as great (as another thing); having the ratio of two and a half to one.
Collocations (1)
Sesquiduplicate ratio (Mathematics) , the ratio of two and a half to one, or one in which the greater term contains the lesser twice and a half, as that of 50 to 20.