No, a space always indicates separate words.
No
Interact Interplay Reciprocate Interchange
Social Interaction can be a word.
They were a group of military babies who served each other in oral butt sex.
There is none in English, not counting compound words.
The word is cohesion. Cohesion is the property of water molecules attracting and sticking to each other.
Dreamt
Boarder
There is some Latin connection, but the word is best known from early French as s'entrevoir, meaning to see each other/visit each other
The word you seek is smitten.
A synonym.
Interdependence.