Definition :A concordancer is computer program which can analyse a corpus of material to search for specific words and expressions and create a list of examples (a concordance) showing how the word is used, its collocations etc.
Example : If you ask the concordancer to search for a specific word or collocation - eg heavy rain - it will search the corpus or corpora that it has at its disposal for all instances of that word/phrase.
Try it out : Go to Lextutor. enter heavy rain (or another word or collocation of your choice) into the Keyword box. Select a corpus from the Choose a Corpus box , then click on Get concordance. The concordancer will produce a list of examples of the use of that word from the corpus. This list is known a a concordance.
Data from a concordancer can be used by the teacher to research how specific language items are actually used. For example : What's most common - to talk about an attitude to something, towardssomething, or toward something? Does it differ between American and British English? Or between written and spoken English? By choosing different corpora and comparing the results, you can work out what are the most common patterns in each case.
Learners can also be encouraged to use a concordancer, or to complete guided discovery activities using concordancesprovided by the teacher, in order to encourage them to work out rules of use for themselves.