Valmiki Ramayana Ayodhya Kanda Sarga 43 Shloka 5
Original Shlokaपातयित्वा तु कैकेय्या रामं स्थानाद्यथेष्टतः। प्रदिष्टो रक्षसां भागः पर्वणीवाहिताग्निना।।2.43.5।।
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कैकेय्या of Kaikeyi, यथेष्टतः according to her whim, रामम् to Rama, स्थानात् from his place, पातयित्वा having thrown down, अहिताग्निना by the sacrificers, पर्वणि on the new moon days, रक्षसाम् to rakshasas, भागः इव like the share, प्रदिष्टः is given.
You have thrown away Rama from his place as per the whim of Kaikeyi, like the share of offering meant for gods given away to rakshasas by the sacrificers on the new Moon days.