abashyoudaoicibaDictYouDict[abash 词源字典]
abash: [14] Abash shares a common ancestry with abeyance [16], although the latter underwent an about-turn in meaning in the 17th century which disguises their relationship. They go back to a Latin verb batāre, meaning ‘yawn’ or ‘gape’. This was borrowed into French as baer, later bayer (it was the source of English bay ‘recessed space’).

The addition of the prefix es- (from Latin ex-) produced esbaer, later e(s)bahir ‘gape with astonishment’, whence, via the present stem e(s)bass-, came English abash, which originally meant ‘stand amazed’ as well as ‘embarrass, discomfit’. (Bashful is a 16thcentury derivative, with elision of the a-, which was first used by the dramatist Nicholas Udall.) Addition of the prefix a- to Old French baer, meanwhile, had given abaer ‘aspire after’, and its noun abeance ‘aspiration, desire’.

In legal terminology, this word was used in French for the condition of a person in expectation or hope of receiving property, but in English the focus quickly became reversed to the property, and its condition of being temporarily without an owner.
=> abeyance, bashful[abash etymology, abash origin, 英语词源]
abash (v.)youdaoicibaDictYouDict
"perplex, embarrass," early 15c., earlier "lose one's composure, be upset" (late 14c.), from Old French esbaiss-, present stem of esbaer "gape with astonishment," from es "out" (see ex-) + ba(y)er "to be open, gape," from Latin *batare "to yawn, gape," from root *bat, possibly imitative of yawning. Related: Abashed; abashing. Bashful is a 16c. derivative.