https://doi.org/10.1351/goldbook.N04249
A nucleophile (or nucleophilic @R05190@) is a @R05190@ that forms a bond to its reaction partner (the @E02020@) by donating both bonding electrons. A 'nucleophilic @S06078@' is a @H02809@ reaction in which the @R05190@ supplying the @E02130@ acts as a nucleophile. For example:
N04249.png
The term 'nucleophilic' is also used to designate the apparent polar character of certain @R05066@, as inferred from their higher relative reactivity with reaction sites of lower @E01986@. Nucleophilic reagents are @L03511@.