"Haddest gander" is an informal phrase that means to take a look or to have a quick glance. There are many synonyms for this phrase that can be used interchangeably, such as "took a peek," "had a peek," "took a glance," "had a glance," or "had a look." Other synonyms that can be used include "took a quick look," "had a quick glance," "had a brief look," "had a swift look," "had a cursory glance," and "had a rapid glance." These synonyms can be used in different situations, depending on the context and the tone of the conversation or writing.