raid 
(rād)
(rād)n.
1. A surprise attack by a small armed force.
2. A sudden forcible entry into a place by police: a raid on a gambling den.
3. An entrance into another's territory for the purpose of seizing goods or valuables.
4. A predatory operation mounted against a competitor, especially an attempt to lure away the personnel or membership of a competing organization.
5. An attempt to seize control of a company, as by acquiring a majority of its stock.
6. An attempt by speculators to drive stock prices down by coordinated selling.
v. raid·ed, raid·ing, raids
v.tr.
To make a raid on.
v.intr.
To conduct a raid or participate in one.
[Scots, raid on horseback, from Middle English rade, from Old English rād, a riding, road; see reidh- in the Appendix of Indo-European roots.]
raider n.
Word History: Raid and road both descend from the Old English word rād, which meant primarily "the act of riding" but could also be used specifically to describe an act of riding with hostile intent—that is, a raid. The ai in raid represents the standard development of the Old English vowel ā in Scots and the dialects of northern England, while the oa in road represents the standard development of Old English ā in the dialects of southern England. In the dialects of southern England, road retained its earlier senses of "journey on horseback" and "hostile foray" until the mid-1600s, when the modern sense "public way" became the most common meaning of the word. Later, Sir Walter Scott (1771-1832) helped popularize the northern form of the word, raid, through his collections of Scots ballads and his other writings. In the meaning "a military expedition on horseback," raid became part of the general vocabulary of English outside of Scotland and northern England. A trace of the earlier meaning of road, "foray, raid," can still be detected in the compound inroad, literally "a riding or advance into."