The Collaborative International Dictionary of English v.0.48:
Flannel \Flan"nel\ (fl[a^]n"n[e^]l), n. [F. flanelle, cf. OF.
flaine a pillowcase, a mattress (?); fr. W. gwlanen flannel,
fr. gwlan wool; prob. akin to E. wool. Cf. Wool.]
1. A soft, nappy, woolen cloth, of loose texture. --Shak.
[1913 Webster]
2. a cotton fabric with a thick nap on one side, resembling
flannel[1]; it is used, e. g. for underwear or sheets;
also called flanellette.
[PJC]
3. pl. garments made of flannel, especially underwear.
[PJC]
4. a washcloth. [Brit.]
[PJC]
5. humbug; nonsensical or evasive talk. [Brit. informal]
[PJC]
6. insincere flattery or praise. [Brit. informal]
[PJC]
Adam's flannel. (Bot.) See under Adam.
Canton flannel, Cotton flannel. See Cotton flannel,
under Cotton.
[1913 Webster] flannelbush