the time required for something to fall to half its initial value (in particular, the time for half the atoms in a radioactive substance to disintegrate)
any of the more or less continuous military expeditions in the 11th to 13th centuries when Christian powers of Europe tried to recapture the Holy Land from the Muslims
go on a crusade; fight a holy war
exert oneself continuously, vigorously, or obtrusively to gain an end or engage in a crusade for a certain cause or person; be an advocate for; "The liberal party pushed for reforms"; "She is crusading for women's rights"; "The Dean is pushing for his favorite candidate"
a diversion that occupies one's time and thoughts (usually pleasantly); "sailing is her favorite pastime"; "his main pastime is gambling"; "he counts reading among his interests"; "they criticized the boy for his limited pursuits"
(psychology) the aggregate of the responses or reactions or movements made by an organism in any situation
the action or reaction of something (as a machine or substance) under specified circumstances; "the behavior of small particles can be studied in experiments"
the psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior; "we did not understand his motivation"; "he acted with the best of motives"
the act of motivating; providing incentive
the condition of being motivated; "his motivation was at a high level"