Yes, phlegmatic has roots in that colorless, mucousy stuff called phlegm, but people who are phlegmatic aren't called that because they have lots of mucus. They are just a little dull in expressing feelings or showing emotion.
Watery.
Adjective S.
showing little emotion; "a phlegmatic...and certainly undemonstrative man"
a.
Watery.
a.
Abounding in phlegm; as, phlegmatic humors; a
phlegmatic constitution.
a.
Generating or causing phlegm.
a.
Not easily excited to action or passion; cold; dull;
sluggish; heavy; as, a phlegmatic person.
Phlegmatic
Watery.
Usage Examples
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