rag week vs sponge

rag week

noun
  • An annual event in many universities where students engage in unusual activities to raise money for charity. 

  • The days of the month when a woman has her period. 

sponge

noun
  • A person who takes advantage of the generosity of others (abstractly imagined to absorb or soak up the money or efforts of others like a sponge). 

  • A piece of porous material used for washing (originally made from the invertebrates, now often made of plastic). 

  • A heavy drinker. 

  • A form of contraception that is inserted vaginally; a contraceptive sponge. 

  • Dough before it is kneaded and formed into loaves, and after it is converted into a light, spongy mass by the agency of the yeast or leaven. 

  • A type of light cake. 

  • A mop for cleaning the bore of a cannon after a discharge. It consists of a cylinder of wood, covered with sheepskin with the wool on, or cloth with a heavy looped nap, and having a handle, or staff. 

  • The extremity, or point, of a horseshoe, corresponding to the heel. 

  • A person who readily absorbs ideas. 

  • Iron ore, in masses, reduced but not melted or worked. 

  • Iron from the puddling furnace, in a pasty condition. 

  • A type of steamed pudding. 

  • Any of various marine invertebrates of the phylum Porifera, that have a porous skeleton often of silica. 

  • A porous material such as sponges consist of. 

  • A nuclear power plant worker routinely exposed to radiation. 

verb
  • To wipe out with a sponge, as letters or writing; to efface; to destroy all trace of. 

  • To suck in, or imbibe, like a sponge. 

  • To clean, soak up, or dab with a sponge. 

  • To take advantage of the kindness of others. 

  • To get by imposition; to scrounge. 

  • To use a piece of wild sponge as a tool when foraging for food. 

  • To be converted, as dough, into a light, spongy mass by the agency of yeast or leaven. 

  • To deprive (somebody) of something by imposition. 

How often have the words rag week and sponge occurred in a corpus of books? (source: Google Ngram Viewer )