Defer
late Middle English (also in the sense ‘put on one side’): from Old French differer ‘defer or differ’, from Latin differre, from dis- ‘apart’ + ferre ‘bring, carry’. Compare with defer2 and differ.
wiktionary
Originally a variant of (and hence a doublet of) differ; from Middle English differren(“to postpone”), from Old French differer, from Latin differō.
From late Middle English differren(“to refer for judgement”), from Middle French déférer, from Latin dēferō.
etymonline
defer (v.1)
"to delay, put off, postpone," late 14c., differren, deferren, from Old French diferer (14c.) and directly from Latin differre "carry apart, scatter, disperse;" also "be different, differ;" also "defer, put off, postpone," from assimilated form of dis- "away from" (see dis-) + ferre "to bear, carry," from PIE root *bher- (1) "to carry." Etymologically identical with differ; their spelling and pronunciation were differentiated from 15c., perhaps partly by association of this word with delay. Related: Deferred; deferring.
defer (v.2)
"yield, offer, render," mid-15c., "leave to another's judgment or determination," from Old French deferer "to yield, comply" (14c., Modern French déférer), from Latin deferre "carry away, transfer, grant," from de "down, away" (see de-) + ferre "to carry," from PIE root *bher- (1) "to carry." Sense of "refer (a matter) to someone" also was in the Latin verb. Related: Deferred; deferring.