May be "split",yea
Unmerging cells
split
immerge
unpleasant
The prefix 'dis-' is used in this sense as 'to do the opposite of', as in 'disallow'. To disconnect, therefore, is to act in the directly opposite of 'connect'.
Construct
Hypo is the opposite of the prefix hyper.
The prefix in the word upgrade is 'up'. The opposite would be downgrade.
The opposite of merciful using a prefix is merciless.
Disobedience
unpleasant
The opposite of sever is conjoin.
Anti-social.
The prefix 'dis-' is used in this sense as 'to do the opposite of', as in 'disallow'. To disconnect, therefore, is to act in the directly opposite of 'connect'.
sub-
You may be going for the word expatriate.
Construct
The opposite prefix of the prefix "meta-" is "pre-".
Hypo is the opposite of the prefix hyper.
The opposite of detach using the prefix ad would be "attach", meaning to connect or fasten something to something else.