COMMERCIAL a.
writing paper, usually about 5 by 7½ or 8 inches. -- Commercial paper, negotiable paper given in due course of business. It includes bills of exchange, promissory notes, bank cheks, etc. -- Commercial traveler, an agent of a wholesale house who travels from town to town to solicit orders.
COMPLAIN v.
To give utterance to expression of grief, pain, censure, regret. etc.; to lament; to murmur; to find fault; -- commonly used with of. Also, to creak or squeak, as a timber or wheel. O lose of sight, of three I most complain! Milton.