Definition - What does Upvote mean?
Upvote is a method on the website Reddit by which users can signal their approval or support for a post. Upvotes move a post towards the top of the site, and they are a way to measure how many people approve of the content that is in a post. While other projects can use a voting system, the term upvoting has been associated with Reddit.
Techopedia explains Upvote
In general, upvoting is used to actively promote the content that its applied to. However, it can also signal that a user is in agreement with the content in the post. Some Reddit segments called subreddits provide specific rules for using an upvote — for instance, a music forum might instruct users to upvote music that they like, or music that is new to them.
In general, an upvote in Reddit is similar to other general use kinds of indicators such as a “Like” on Facebook. These types of indicators need clear and concrete rules for consistent application. Project engineers try to make the interface as clear and transparent as possible to prevent confusion and increase participation.