ex·pres·sion (k-sprshn)
1. The act of expressing, conveying, or representing in words, art, music, or movement; a manifestation: an expression of rural values.
2. Something that expresses or communicates: Let this plaque serve as an expression of our esteem.
3. Mathematics A symbol or combination of symbols that represents a quantity or a relationship between quantities.
4. The manner in which one expresses oneself, especially in speaking, depicting, or performing.
5. A particular word or phrase
[...]
Of course, you could nonetheless be right, and I've been perhaps misled by the similar italian (and french) "expressions": espressione (fr. expression)
What do you think thereof?
Can anyone understand me, if I use "expression" in the way I used it?
Can anyone suggest me any substitute (phraseology, formula, syntagma, locution, term, etc.)?

"I read this _ _ _ _ _ on a sms"

thank you