on the sly
US /ɑn ðə slaɪ/
UK /ɑn ðə slaɪ/
1.
diam-diam, sembunyi-sembunyi, secara rahasia
doing something secretly or furtively
:
•
He was eating cookies on the sly when his mom wasn't looking.
Dia makan kue diam-diam saat ibunya tidak melihat.
•
They were meeting on the sly to plan the surprise party.
Mereka bertemu diam-diam untuk merencanakan pesta kejutan.
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