Momentary misunderstanding, minor embarrassment. When the Shingata Flu (新型インフルエンザ) started, my future father-in-law was very concerned about preventative measures. He told me to avoid areas of hitogomi, which shocked me a bit.
My thinking went, “Hito is person, gomi is trash. Wait, he is far to kind to refer to people that way.” Actually komu (込む) is ‘to be crowded’, komi is a noun made from the verb, and when we tie words together, the first sound of the trailing word often gets modified to ease pronunciation. Hence, hitogomi (人込み) is a crowd.
As expected, he was being polite, but a little worrisome: he was merely warning me to avoid crowds. Of course, I ride the train to work in the morning and teach hundreds of kids at different schools every day, so I have no way to comply with his directive.