横断歩道って英語でなんて言うの？

Both words have the same meaning, but crosswalk is more commonly used referring the marked off areas that people can walk across. So if you're looking for a safe place to cross the road you can ask "where is the closest crosswalk".

In America we call it the cross walk. It is indicated with signs and with white stripes going across the road from one sidewalk to another, commonly at a stop light. In the UK they refer to these areas as "zebra crossing", probably because of the white stripes on the dark road. Technically, also found in traffic books and official documents, is "pedestrian crossing". The pedestrian crossing is self explanatory and understood in all the English speaking countries because a pedestrian is a person who is walking or traveling by foot. A crossing is a general term for anything that crosses something else, even a bridge that crosses the river or another street.

In the US a place where pedestrians cross the road is called a "crosswalk" however in the UK it is referred to as a "zebra crossing" because of the white and black striped pattern on the road.

In America (US) the part of the road you can cross over on when walking is called a crosswalk but in the UK we refer to it as a pedestrian or zebra crossing instead. A pedestrian/zebra crossing usually has white/black lines to show that's where to cross safely and sometimes even has traffic lights to make it safer to cross.

The part of the road where pedestrians are meant to cross is called a "crossway" or a "pedestrian crossing". For example, you can say: -Jaywalking is not allowed in our city. People are only allowed to use the pedestrian crossing/crossway.

Pedestrian crossing is commonly used in English speaking countries and will be easily understood. Zebra crossing is used in Australia and England because of the stripes marked on the section a person should cross the road.