The exclusion of a word, or several words, in a reference, or several references, has no relationship to the validity of any other word.
Perhaps is not the spelling of the author, but the vocabulary of the critic.
That, in effect, changes two letters. Seeing it from your perspective, both the a and the r had to move, else there would be no room between the w and the a.
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Meaning of TOST
Webster's 1913 Dictionary
Definition:
\Tost\,
imp. & p. p. of Toss.
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Meaning of LOTH
Pronunciation: lowth
WordNet Dictionary
Definition: [adj] unwillingness to do something contrary to your custom; "a reluctant smile"; "loath to admit a mistake"; "unwilling to face facts"