condense v.

word-forming element usually meaning "with, together," from Latin com, archaic form of classical Latin cum "together, together with, in combination," from PIE *kom- "beside, near, by, with" (compare Old English ge-, German ge-). The prefix in Latin sometimes was used as an intensive.

Before vowels and aspirates, it is reduced to co-; before -g-, it is assimilated to cog- or con-; before -l-, assimilated to col-; before -r-, assimilated to cor-; before -c-, -d-, -j-, -n-, -q-, -s-, -t-, and -v-, it is assimilated to con-, which was so frequent that it often was used as the normal form.

early 15c., "closely compacted, thick," from Latin densus "thick, crowded; cloudy," which is of uncertain etymology, perhaps related to Greek dasys "hairy, shaggy; thick with leaves," as a grammatical term, "aspirated," but even this is in doubt. Figurative sense of "difficult to penetrate" (of writing, etc.) is from 1732; that of "stupid" is first recorded 1822. Related: Densely; denseness.