rig·or·ous 
(rĭgər-əs)
(rĭgər-əs)adj.
1. Characterized by or adhering to strict standards or methods; exacting and thorough: a rigorous study of the medication; a rigorous researcher.
2.
a. Harsh, severe, or demanding: a rigorous taskmaster; a rigorous schedule.
b. Very unpleasant or inclement: a rigorous climate.
3. Adhering strictly to a belief or ideology; uncompromising or inflexible: a rigorous Catholic; a rigorous sense of correctness.
rigor·ous·ly adv.
rigor·ous·ness n.
- insularly
- insulate
- insulation
- insulative
- insulator
- insulin
- insulin aspart
- insulin-dependent diabetes
- insulin-dependent diabetes mellitus
- insulin detemir
- insulin glargine
- insulin glulisine
- insulin-like growth factor
- insulin lispro
- insulin pen
- insulin pump
- insulin resistance
- insulin shock
- insult
- insulter
- insultingly
- insuperability
- insuperable
- insuperably
- insupportable