Learn how to say Heliotropism correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word heliotrope:
a plant of the borage family, cultivated for its fragrant purple or blue flowers which are used in perfume.
Genus Heliotropium, family Boraginaceae
[mass noun] a light purple colour, similar to that of heliotrope flowers.
Old English eliotropus (originally applied to various plants whose flowers turn towards the sun), via Latin from Greek hēliotropion ‘plant turning its flowers to the sun’, from hēlios ‘sun’ + trepein ‘to turn’. The spelling was influenced by French héliotrope