All 3 Uses

rigorous
in
We Beat the Street
(Edited)

Usually students had difficulty adjusting to the rigorous classes, especially if they had not attended University the first two years, but Rameck slid in easily and made good grades from the beginning.
Chpt 9

rigorous = difficult and demanding
A couple of weeks later, after Rameck had complained about the rigors of the program one too many times for Carla, she stopped him after class.
Chpt 16

rigors = difficulties (things that are difficult and demanding)
George, Sampson, and Rameck now felt a lot more confident about facing the rigors of college work and thankful that their parents and teachers could once again applaud for them as they reached another milestone.
Chpt 16 *

Definitions:

(1) (rigorous as in: we follow a rigorous procedure)
thorough and careful procedures
(2) (rigorous as in: a rigorous math class)
difficult and demanding
(3) (rigorous as in: rigorous enforcement)
strict when enforcing rules
(4) (meaning too rare to warrant focus)