submerge vs overwhelm

submerge and overwhelm both are verbs.

Word	Noun	Adjective	Verb	Adverb
submerge	No	No	Yes	No
overwhelm	No	No	Yes	No

As verbs, submerge and overwhelm are synonyms defined as:

Other synonyms of submerge include drown.

submerge (verb)	overwhelm (verb)
fill or cover completely, usually with water	charge someone with too many tasks
cover completely or make imperceptible	overcome by superior force
put under water	cover completely or make imperceptible
sink below the surface; go under or as if under water	overcome, as with emotions or perceptual stimuli