deferyoudaoicibaDictYouDict[defer 词源字典]
defer: English has two distinct verbs defer. The one meaning ‘delay’ [14] is ultimately the same words as differ. It comes via Old French differer from Latin differre ‘carry apart, delay’, a compound verb formed from the prefix dis- ‘apart’ and ferre ‘carry’ (related to English bear). The Latin verb’s past participle, dīlātus, is the source of English dilatory [15]. Defer ‘submit’ [15] comes via Old French deferer from Latin dēferre ‘carry away’, a compound verb formed from the prefix - ‘away’ and ferre.

The notion of submission seems to have arisen from an earlier application to referring, or ‘carrying’, a matter to someone else.

=> bear, dilatory[defer etymology, defer origin, 英语词源]
defer (v.1)youdaoicibaDictYouDict
"to delay," late 14c., differren, deferren, from Old French differer (14c.), from Latin differre "carry apart, scatter, disperse;" also "be different, differ;" also "defer, put off, postpone," (see differ). Etymologically identical with differ; the spelling and pronunciation differentiated from 15c., perhaps partly by association of this word with delay.
defer (v.2)youdaoicibaDictYouDict
"yield," mid-15c., from Middle French déférer (14c.) "to yield, comply," from Latin deferre "carry away, transfer, grant," from de- "down, away" (see de-) + ferre "carry" (see infer). Main modern sense is from meaning "refer (a matter) to someone," which also was in Latin.