Up and to are always two separate words. There is no such word as upto.
It is used as one word.
no it is not an one word it is of two word
Hipbone is one word.
The word "hairbrush" is typically written as one word, not two.
One word, two syllables
It is one word.
It is one word.
"Hardworking" is one word.
Toenail is one word.
It can either be one word (seashell) or two (sea shell)
"Doorway" is one word.
It is one word.