It depends on the region. In the southern states, the terminology is much more loose. "Freezing" just means "below 55F". "Below zero" can mean anything under 3

It depends on the region. In the southern states, the terminology is much more loose. "Freezing" just means "below 55F". "Below zero" can mean anything under 32F, it's very ambiguous (some use this correctly, some do not). Usually if it's actually below freezing, people will be very excitedly telling you about the frost they saw on the grass in the morning! Northern states differentiate between ("below zero" / "negative temperatures") vs. "below freezing". Actually some northern states often omit the "below" in "below freezing" and just say "it's freezing" and people will correct you if its 35F and you use "its freezing outside" to colloquially mean that you personally feel its very cold outside: "It's above freezing actually, not much ice to worry about." In the northern states, if it's -40F outside people's eyes will turn into daggers as they tell you, "It's dangerously cold outside right now. Are you sure you need to go out? Take this extra clothing/blanket/etc. Is your cell phone charged? Will your car have trouble making it? I can drive you."