there should be a word for....
....that thing when you're talking to someone you don't know very well and they're all cagey and cold, until they find a way to drop the words "my boyfriend" or "my fiance" into the conversation, and THEN they start talking to you. Usually it's women, who are understandably worried about getting hit on, but guys have given me the same tipoff, because, I dunno, I have a gay-looking upper lip or something. Most stange women, or women strangers, have no way to know that I am So Ridiculously Bad at hitting on people, and am actually relieved when they oh-so-subtly mention their attachment, because it drops the expectations even lower and affords the chance for a real conversation. Recently in a bar I was chatting awkwardly with someone, and after she got the "my husband" name-drop out of the way, she really opened up, rambling stories, expressive body language and everything. So I think there really should be a word for this little anti-pickup maneuver. There probably is one in some dating book. Just like there probably is a single word for "politely dropping the hammer on your dreams."