What does the prefix plac mean? - PREFIXES AND SUFFIXES

"dis" here means "not" as in "Not loyal"

Prefixes and suffixes are grammatical and lingual "affixes." Prefixes are affixed before and suffixes after a base word or word stem to add information. For example, with the word "prehistoric," the prefix is "pre-" meaning "before," the base word is "history" meaning "recorded events and knowledge", and the suffix is "-ic" meaning "relating to the science of."
In other words, "prefix" simply refers to an attachment before or in front of, in this case, a shorter word or stem. In lingual terms, a "stem" is the main part of a word to which prefixes and suffixes can be added and may not necessarily be a word itself, such as "dod" in "doddle."
Similarly, "suffix" refers to an attachment after the end of an existing word or stem, serving to form a new word or functioning as an inflectional ending, for example, "s" or "es" to make for plurality.

beware wishing harm on other's ,can come back to you ten fold .then it what is claimed to happen.

What DOES the prefix "mito-" mean?

Air does not have a prefix. Do you mean to ask is there is a prefix that means "air"?
Like aeroplane or aerodrome? Aeronaut?

Compose does not have a suffix. It may be considered to have a prefix, which would be "com-". Com- as a prefix usually means "together."

It is not a prefix!

Segregation
Segregate
"se" is the prefix meaning: "from" or "away"
"greg" is the root of the word meaning "group" or "united" or "union"
"tion" is the suffix meaning "result of" or "state of" or "act of"
"ate" (for segregate) would be the suffix meaning: "make" or "cause".
Hope this helped!

veris is not the prefix
verisimili= very truthful, here veri is not a prefix but actually the rootword