Halliday & Matthiessen (1999: 273):
Since we are suggesting that grammatical metaphor is not simply an alternative realisation of the same meanings, but a distinct construing of experience in which there is junction of semantic features (have a bath, do a turn may be "dead metaphors", but in bring about a conclusion there is clearly a junction between the 'process' meaning of 'conclude' and the 'thing' meaning of noun), we could expect to find this same phenomenon in lexical metaphor: that the 'literal' meaning of the transferred term would remain, in junction with the features acquired in its metaphorical environment. Just as, in bring about a conclusion, conclusion combines the category (word class) meanings of verb and noun, so in get a handle on the concept, handle combines the item (word) meanings of handle and idea.