sub- (also suc- before c;suf- before f; sug- beforeg; sup- before p; sur-before r; sus- before c, p,t)*prefix1. at, to, or from a lower level or position: sub-alpine.>lower in rank or importance: sub-deacon.2. somewhat; nearly, more or less: sub-Antarctic.3. denoting subsequent or secondary action of the same kind: subdivision.4. denoting support:subvention.5. Chemistry in names of compounds containing a relatively small proportion of a component: sub-oxide.-originfrom L. sub ‘under, close to’.
ob- (also oc- before c; of-before f; op- before p)*prefix forming words of mainly Latin origin meaning:1. to, towards: obverse.2. against; blocking:opponent.>concealment:occult.3.finality or completeness:obsolete.4.technical in a direction or manner contrary to the usual: obconical.-originfrom L. ob ‘towards, against,in the way of’.
in-1(also il- before l; im-before b, m, p; ir- before r)*prefix 1. (added to adjectives) not:infertile.2. (added to nouns) without;a lack of: inappreciation.-originfrom L.
in-2(also il- before l; im-before b, m, p; ir- before r)*prefix in; into; towards;within: influx.-originrepresenting IN or the L.prep. in.
ab- (also abs-)prefix away; from: eg. abdicate.-originfrom L.
de-prefix1.(forming verbs and their derivatives) down; away: eg. descend | deduct. completely: denude.2.(added to verbs and their derivatives) denoting removal or reversal: eg. de-ice.3.denoting formation from: eg. de-verbal.-originfrom L. de ‘off, from’; sense2 via OFr. des- from L. dis-.
com- (also co-,col-,con-, or cor-)prefix with; together; jointly; altogether: eg.combine.-originfrom L. cum ‘with’.