invisible ink
noun
Origin of invisible ink
First recorded in 1675–85
Words nearby invisible ink
inviscid,
invisible,
invisible balance,
invisible glass,
invisible hand,
invisible ink,
invisible man,
invisible man, the,
invisible shadow,
invitation,
invitational
British Dictionary definitions for invisible ink
invisible ink
noun
a liquid used for writing that does not become visible until it has been treated with chemicals, heat, ultraviolet light, etc