cad＝to fall（落下） 变化型 cid，cas
1 [esp attrib 尤作定语] happening by chance 偶然的; 碰巧的
*a casual encounter, meeting, visit, etc 邂逅、不期而遇、不意的拜访.
2 (a) [esp attrib 尤作定语] made or done without much care or thought; offhand 不经意的; 随便的; 马虎的; 临时的
*a casual remark 漫不经心的话.
(b) (derog 贬) showing little concern; nonchalant; irresponsible 漠不关心的; 无动于衷的; 不负责任的
*His attitude to his job is rather casual. 他的工作态度不太认真.
(c) [esp attrib 尤作定语] not methodical or thorough; not serious 无条理的; 不彻底的; 不认真的
*a casual inspection 草率的检查
* a casual glance at a book 胡乱看一本书
* a casual observer, reader, etc 马虎的观察者、读者等.
3 (of clothes) for informal occasions; not formal （衣物）便服的, 非正式的
*casual wear 便装.
4 [attrib 作定语] not permanent; irregular; part-time 非永久的; 不定期的; 部分时间的
*earn one's living by casual labour 靠做短工为生
* a casual labourer 临时工
* casual sex, ie not involving a lasting relationship 萍水相逢的性行为（非持久的关系）.
5 [attrib 作定语] slight; superficial 轻微的; 表面的; 肤浅的
*a casual acquaintance泛泛之交.
1【relaxed】2【not formal】3【work】4【relationship】5【without attention】6【not planned】7【not regular】
1300-1400; Language: Old French;Origin:
casuel, from Late Latin
casualis, from Latin
relaxed and not worried, or seeming not to care about something a casual manner His eyes were angry, though he sounded casual. Marsha was quite casual about appearing on TV. She had a casual attitude to life.【NOT FORMAL】
not formal or not for a formal situation
≠ formal Jean felt more comfortable in casual clothes . a casual jacket【WORK】
employed as a temporary worker or working for only a short period of time casual labour staff employed on a casual basis Chris has occasional casual work but mostly he is unemployed.【RELATIONSHIP】
knowing someone or having sex with someone without wanting a close relationship with them
≠ serious She will never be more than a casual acquaintance. They had been conducting a casual affair for years. John just wanted casual sex .【WITHOUT ATTENTION】
without any serious interest or attention He gave us a casual glance as he walked by, but didn't stop. To the casual observer (=to someone who is not looking carefully) Mary seemed quite calm.【NOT PLANNED】 [only before noun]
happening by chance without being planned a casual conversation He made some casual remark (=one without thinking much about it) about her holiday.【NOT REGULAR】 [only before noun]
doing something or using something sometimes but not regularly or often
= occasional a casual drug user The museum is of great interest, both to experts and to casual visitors.>casuallyadv a casually dressed young man 'Where do you work?' she asked casually. He walked down the road, casually swinging his bag.>casualnessn[U]
1. The Love Family is either too casual for children — your friends have no obligation to provide for them — or it's too unstable, with adults moving on if the relationship no longer answers their search for perfect happiness. "情爱家庭"对孩子来说，要么太随意 —— 新的伴侣对你的孩子没有抚养责任，要么太不稳定，成年人一旦感到他们的关系无法满足自己对完美幸福的追求，就会转而他求。
2. His attitude to his job is rather casual. 他的工作态度不太认真.
3. He noticed at once that discipline was slack: the Danes had the self-confidence of conquerors, and their security precautions were casual. 他马上发现丹麦军纪律松弛，他们以征服者自居，安全措施马马虎虎。
4. "How was school today?" I asked, acting very casual. "今天学校上课怎么样？"我装作漫不经心地问他。
5. “Hi.” I tried to be casual. “My name is Liu Zongren. I come from Beijing, China.” “你好！” 我想随便点。“我叫刘宗仁。我来自中国北京。”
6. “In Africa, an eighteen-year-old woman might need a job because she had a baby before marriage and has only a casual relationship with the father, or she might have a husband who goes on to another marriage and supports the children of that union.” "在非洲，18岁的女子就可能需要一份工作，因为她还未结婚就生了孩子，而她与孩子的父亲只有一种若即若离的关系，或者她的丈夫可能另外结婚，需要负担婚内生的孩子。"
7. Casual conversation tends to be filled with repetitions and pauses. 随意的交谈中常常有许多重复和停顿。