A small suburban home or apartment, kept in an unclean and usually unsanitary state, where people are free to come and leave as they please, sleeping there, partying there, whatever. Such places are usually frequented by punk rock bands on their way through town due to their low cost and the party-like atmosphere, which is where the name came from. Despite how it may sound, punkhouses are rarely inhabited by your typical "hobo", and long-term residents are usually in their late teens.