offhand

形容词 offhand:

1. with little or no preparation or forethought
   同义词：ad-lib, extemporaneous, extemporary, extempore, impromptu, offhanded, off-the-cuff, unrehearsed
2. casually thoughtless or inconsiderate
   同义词：offhanded

副词 offhand:

1. without previous thought or preparation
   同义词：offhanded, offhandedly
2. in a casually inconsiderate manner
   同义词：offhanded, offhandedly

1. He's a good salesman, but his offhand manner does tend to put people off.
   他是个很好的推销员，可是他那随便的态度容易使人产生反感。
2. I'm talking offhand, simply speaking my mind.
   我这是信口开河，随便谈谈脑子里想的东西。

off.hand

adv.（副词）
Without preparation or forethought; extemporaneously.
未经准备地：没有准备或事先思考；即席地
adj.also （形容词） 也作
offhanded
Performed or expressed without preparation or forethought.See Synonyms at extemporaneous
即席表演的：没有准备或事先思考而表演或表达的参见 extemporaneous

【引伸】
off.hand.edly
adv.（副词）
off.hand.edness
n.（名词）