On The Way
En Route, In The Middle Of, Half Done
noun
If you're in the middle of the planned route you're on the way / en route.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
「今すぐに来られますか？」「ええ。今向かっている途中です。」「え？ということは、場所をご存知なんですね？」「いいえ、分かりません。」
"Can you come over right now?" "Sure, I’m actually on my way now." "Huh? Do you know where you’re going?" "Nope, I don’t."