The opposite of the verb "post" is take down, remove, delete.The opposite of a fence post would be the horizontal support, or the rail.The opposite prefix of post- (after) is pre- (before, prior).
Hypo is the opposite of the prefix hyper.
the prefix post means after
The opposite prefix of the prefix "meta-" is "pre-".
the prefix of counteract is opposite
The prefix in the word upgrade is 'up'. The opposite would be downgrade.
The prefix un- makes the word "unsuitable."
Yes, unlike does have that prefix. The prefix is un-.
Rational is the opposite of irrational. The ir- prefix is a variation of the in- prefix and means "not".
The opposite form of the word "expendable" by adding a prefix is unexpendable.
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The true opposite of prefix is no prefix.But, as a prefix means something added at the start of a word. the generally understood opposite is suffix - which is something added to the end of a word.