paraffin (n.) Look up paraffin at
1838, from German Paraffin, coined c. 1830 by German chemist Karl von Reichenbach (1788-1869), who first obtained it as a waxy substance from wood tar, irregularly from Latin parum "not very, too little," probably related to parvus "little, small" (from PIE root *pau- (1) "few, little") + affinis "associated with" (see affinity).

So called because paraffin is chemically not closely related to other substances. The liquid form (originally parafin oil) Reichenbach called eupion, but this was the standard meaning of paraffin in English by 1860.