gerundive neuter singular nominative of samiñjati (should be contracted; see note)
Analysis. sam- (together) + iñj- (bend, draw) + -itabbaṁ (gerundive ending, expressing what ought or should be done). The surface form samiñjitabbaṁ contracts the gerundive suffix -itabba with the neuter nominative ending -ṁ, yielding the sense 'what should be brought together or contracted'.
Etymology. sam- + √iñj (bend, contract). The root iñj appears in Sanskrit iñjati 'moves, stirs'; the prefix sam- brings the sense of gathering inward, as when objects are drawn together or a limb is flexed.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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