(1) ven can be used for "be nerdy," but there may be some other apt English translations. It describes someone who is really into something (or a number of things), a true devotee, who partakes in activities associated with whatever he/she is into -- doesn't just sit on the sidelines -- and does so very seriously (though, with Klingons, pretty much everything is done very seriously by everybody, so this isn't much of a distinction). It is possible to say venwI' "one who is nerdy" or "nerd."