This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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n. The principal spring in a mechanical device, especially a watch or clock, that drives the mechanism by uncoiling.

n. The chief motivating force: the mainspring of a reform movement.

n. The principal spring of a clockwork mechanism, that drives it by uncoiling.

n. The most important reason for something.

n. The principal or most important spring in a piece of mechanism, especially the moving spring of a watch or clock or the spring in a gunlock which impels the hammer.

n. The principal spring of any piece of mechanism, as, in a gun-lock, the spring which operates the hammer; specifically, the coiled spring of a watch or other timepiece.

n.

n. The impelling cause of any action; the inciting motive.

n. the most important spring in a mechanical device (especially a clock or watch); as it uncoils it drives the mechanism

"When the spiritual stage of her evolution is reached, this occult process must become the whole process; to get through the veil of forces and get at their secret mainspring, which is the Spirit itself, is of cardinal importance."

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outskirt    imperfectness    rottenest    by-law    progressivism    syndicalism    logbook    altruist    transitoriness    hour hand