Is adding the word "solution" necessary when listing the materials used in a synthesis?
No, the repeated addtion of the word "solution" is not needed.

All you want here is to provide a measured quantity (e.g., volume), concentration of your reagent in the solvent, and inferred quantity (e.g., mmol).  This may be reported in the following pattern, too:


  "1-Cinnamyl-4-methylbenzene (4a): The compound 4a was synthesized from
  1-methoxy-4-{[(2 E)-3-phenylprop-2-en-1-yl]oxy}benzene 2b ($\pu{240.9 mg}$,
  $\pu{1.00 mmol}$) with p-tolylmagnesium bromide 3a ($\pu{1.4 mL}$, $\pu{1.1 M}$ in THF, $\pu{1.5 mmol}$) in the presence of 1b ($\pu{4.1 mg}$, $\pu{1 mol\%}$) in $\ce{Et2O}$ ($\pu{5 mL}$) at room temperature for $\pu{24 h}$ ($\pu{198.0 mg}$, $\pu{95\%}$ yield, colorless liquid)."


(source: Hashimoto et al. in Molecules 2019, 24, 2296 (doi.org/10.3390/molecules24122296), section 3.2; open access publication.)

This pattern is seen for inorganic reagents like $\ce{HCl}$ dissolved in water, yet equally available in methanol, 1,4-dioxane, etc. (example); and organometallic reagents, e.g. butyllithium, methylmagnesium bromide.