Colon: dictionary key-value pair delimiter

In a Dictionary type, data, consists of a semicolon delimited list of keys and their values. For each such list item, the key and its value are separated by a colon. Generically:

dictionary("key:value; key:value"); 

Thus, in current form:

$MyDictionary = {apple:fruit;pear:fruit;pea:vegetable}; 

and old form (both forms work):

$MyDictionary = dictionary("apple:fruit;pear:fruit;pea:vegetable"); 

Noting that whitespace in the dictionary data either side of colons and semicolons is ignored, but not within a key name or value. Keys ideally should be a single word: