Definition of knack. 1  1 : a special ready capacity that is hard to analyze or teach. 2  2a : a clever trick or stratagemb : a clever way of doing something. 3  3 archaic : an ingenious device; broadly : toy, knickknack.
Medical Definition of gingivoplasty. plural. gingivoplasties. : a surgical procedure that involves reshaping the gums for aesthetic or functional purposes.
Medical Definition of SPORANGIUM. : a structure (as of an alga or fungus) within which spores are produced.â spoÂ·ranÂ·gial \-j(Ä-)Él\ adjective.efinition of SPORANGIUM. : a structure within which spores are produced. â spoÂ·ranÂ·gial \-j(Ä-)Él\ adjective. See sporangium defined for kids.