De-lexicalised verbs are verbs that have little meaning alone but that can be joined together with many other words, so generating a wide variety of new meanings. These have also been called 'empty' verbs.

Example
'Get' is a common example of this. 'Get' does not have one single meaning but can be linked with many other words to generate meanings, e.g. get in, get away, get married, get paid, get older, get more difficult etc.

In the classroom
Learners often have problems with these verbs because they try to find a general meaning. They also struggle to find the right collocation, often translating possible equivalents from their own language. An example of this is the confusion caused by the de-lexicalised verbs 'make' and 'do'.

Further links:

https://www.teachingenglish.org.uk/article/phrasal-verbs-get