[an.neal] vb [ME anelen to set on fire, fr. OE onaelan, fr. on + aelan to set on fire, burn, fr. al fire; akin to OE aeled fire, ON eldr] vt (1664) 1 a: to heat and then cool (as steel or glass) usu. for softening and making less brittle; also: to cool slowly usu. in a furnace b: to heat and then cool (nucleic acid) in order to separate strands and induce combination at lower temperature esp. with complementary strands of a different species
2: strengthen, toughen ~ vi: to be capable of combining with complementary nucleic acid by a process of heating and cooling