Not Thinking Before Speaking

Embarrassing moment of the week: So everyday in my class we do some sort of word work. Yesterday we did 'Guess the Covered Word'. I had this paragraph up on the overhead with some words covered up. Then as we read the paragraph we would try to guess the word that was covered by using context clues. Usually I will give them a few guesses at a word and write their guesses on the board. Then I give them a clue by uncovering the first letter and then erase the words that don't match so far and we think of more words that match the first letter and so on. Well, on one word I let them guess for a while and then uncovered the first letter which was a 'f'. Then before really thinking about it I asked the class. "Ok, here is your clue. Now can anyone think of any 'f' words?" Of course the whole class just started laughing and saying "Oh my gosh!! Did you hear what teacher asked us?!" And to make it worse just as I said that another teacher walked in the room to asked me something. The word I was trying to guide them to was 'fantastic'.