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यत्तु कृत्स्नवदेकस्मिन्कार्ये सक्तमहैतुकम् ।
अतत्त्वार्थवदल्पं च तत्तामसमुदाहृतम् ॥१८- २२॥

yattu kRRitsnawadekasminkaarye saktamahaitukam ।

atattwaarthawadalpaM cha tattaamasamudaahRRitam ॥१८- २२॥

Source: Automatic ITRANS Transliteration

But that exclusive work which captivates as if all, purposelessly,
Unprincipled and trivial, that exemplifies tamas.

Source: Milind S. Pandit

Knowledge by which one clings to one single effect (such as the body) as if it is everything, and which is irrational, baseless, and worthless; such knowledge is declared to be Taamasika.

Source: The Bhagavad-Gita: The Sacred Song

And that knowledge by which one is attached to one kind of work as the all in all, without knowledge of the truth, and which is very meager, is said to be in the mode of darkness.

Source: Bhagavad Gita As It Is