Verb (5-dan, ぐ, transitive)
1.  to pour (into)
2.  to sprinkle on (from above);  to water (e.g. plants);  to pour onto;  to spray
3.  to shed (tears)
4.  to concentrate one's energy (strength, attention, etc.) on;  to devote to;  to fix (one's eyes) on
Verb (5-dan, ぐ, intransitive)
5.  to flow into (e.g. of a river);  to run into;  to drain into
6.  to fall (of rain, snow);  to pour down