An adjective denoting an absolute or extreme state or quality does not logically admit of quantification or comparison. Thus, we do not, or should not, say deadest, more perfect, or somewhat unique. It is generally acceptable, however, to modify adjectives of this kind with adverbs such as almost, apparently, fortunately, nearly, probably, and regrettably. Listed below are words that should not be used with a comparative (more, less), superlative (most, least), or quantifying (quite, slightly, very) modifier.
complete [but: almost or nearly complete]
perfect [but: almost or nearly perfect]
fatal [but: almost or nearly fatal]
unanimous [but: almost or nearly unanimous]
full [but: half full, nearly full]
Note: In general, superlatives should be avoided in scientific writing.