# [Tex/LaTex] Delta-equal to symbol

relation-symbolssymbols

How do you write the equal-to symbol with delta on top ("delta-equal to")? One similar to http://www.decodeunicode.org/de/u+225c. Are special packages required for that?
It is supposed to be used for definition of equalities, similar to :=.

How about \triangleq from the AMS fonts? Loading \usepackage{amssymb} will make the command available