What is what does it mean when a guy says night instead of goodnight?

When a guy, or anyone for that matter, says "night" instead of "goodnight," it often conveys a more casual or informal tone. The omission of "good" doesn't necessarily change the underlying sentiment of wishing someone well as they end their day. Here are a few considerations:

1. Casual Relationship: Using "night" might indicate a relaxed or familiar relationship. It suggests a sense of ease between the two people.

2. Brevity and Convenience: Sometimes, people opt for shorter expressions out of convenience, especially in text messaging or social media interactions, where brevity is often preferred.

3. Tone and Context: The tone matters a lot. If the person has been using friendly or warm language before saying "night," it's probably meant to be light-hearted. On the other hand, if the conversation was tense, the brevity might reflect that mood.

4. Cultural or Personal Preference: Different cultures and individuals might have varying norms or personal preferences about how they say goodbye for the evening. For some, "night" might be the standard expression.

5. Level of Intimacy: For some, a simple "night" reflects a more intimate way of speaking, highlighting closeness without the need for formality.

Overall, without additional context, it's difficult to ascertain the exact meaning, but in most cases, using "night" instead of "goodnight" is simply a personal choice and not necessarily indicative of any particular feeling or sentiment.