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to change from a solid state to a liquid state due to heat
The chocolate melted in the microwave.
The chocolate turned from solid to liquid when heated in the microwave.
The snow melted as temperatures rose.
The snow turned into water as the weather got warmer.
This is the most common meaning of 'melt.'
to become emotionally overwhelmed or soften in attitude
She melted when she saw the puppy.
She became emotionally overwhelmed with affection when she saw the puppy.
His heart melted when he heard the sad story.
He became emotionally soft and sympathetic after hearing the sad story.
This figurative meaning is often used to describe emotional reactions.
Remember that 'melt' can be used both literally (e.g., ice melting) and figuratively (e.g., a heart melting with emotion).
The verb 'melt' does not require an auxiliary verb in the present tense (e.g., 'The ice melts in the sun,' not 'The ice is melts in the sun.').
From Middle English 'melten,' from Old English 'meltan,' from Proto-Germanic 'meltaną,' meaning 'to melt, dissolve.' Related to Old Norse 'melta,' Old Frisian 'melta,' and Dutch 'smelten.'
The verb 'melt' is often used in both literal and figurative contexts. In literal contexts, it refers to the physical process of a solid turning into a liquid. In figurative contexts, it can describe emotional reactions or the gradual disappearance of something.