adherent (adj.) Look up adherent at Dictionary.com
late 14c., "sticking, clinging to, adhesive," from Old French adherent or directly from Latin adhaerentem (nominative adhaerens), present participle of adhaerere "stick to," from ad- "to" (see ad-) + haerere "to stick" (past participle haesus; see hesitation).
adherent (n.) Look up adherent at Dictionary.com
early 15c., "follower, supporter, one who upholds (a leader, cause, etc.)," from Old French adherent or directly from Latin adhaerentem (nominative adhaerens), present participle of adhaerere "stick to," from ad "to" (see ad-) + haerere "to stick" (see hesitation). Meaning "adhesive substance" is from 1912.