"Having a gander" is a colloquial expression that means to take a look or observe something. There are various synonyms that can be used to convey the same meaning, such as "having a peek", "taking a glance", "checking out", "surveying", "inspecting", and "examining". These words can be used depending on the context, formal or informal situation and the object of the observation. For example, if someone is peeping through a small window, it would be more accurate to say they are "having a peek" rather than "examining" the object. The use of synonyms can help to vary the language and avoid repetitive sentences.