The state of feeling slightly ill or unwell.
Feeling sickishnesses is not very good, but it's not very bad either.
Examples:
Her sickishnesses made her stay home from school.
I don't like the sickishnesses I feel after eating too much candy.
The medicine helped with my sickishnesses.
The thought of eating snails gives me sickishnesses.
His fear of spiders is a sickishnesses that makes him scream.
The roller coaster gave me sickishnesses, but I still liked it.