1.  sentimental(s = adj.all) - given to or marked by sentiment or sentimentality;
Derived forms noun sentiment₁, noun sentimentality₂

2.  sentimental(s = adj.all) bathetic, drippy, hokey, kitschy, maudlin, mawkish, mushy, schmaltzy, schmalzy, slushy, soppy, soupy - effusively or insincerely emotional; "a bathetic novel"; "maudlin expressions of sympathy"; "mushy effusiveness"; "a schmaltzy song"; "sentimental soap operas"; "slushy poetry"
Derived forms noun sentiment₁, noun sentimentality₁

1.  Having, expressing, or containing a sentiment or sentiments; abounding with moral reflections; containing a moral reflection; didactic. [1913 Webster]
"Nay, ev'n each moral sentimental stroke,
Where not the character, but poet, spoke,
He lopped, as foreign to his chaste design,
Nor spared a useless, though a golden line." [1913 Webster]

2.  Inclined to sentiment; having an excess of sentiment or sensibility; indulging the sensibilities for their own sake; artificially or affectedly tender; -- often in a reproachful sense. [1913 Webster]
"A sentimental mind is rather prone to overwrought feeling and exaggerated tenderness." [1913 Webster]

3.  Addressed or pleasing to the emotions only, usually to the weaker and the unregulated emotions. [1913 Webster]

sentimental, adj.
1 of or characterized by sentiment.
2 showing or affected by emotion rather than reason.
3 appealing to sentiment.

Idiom:
sentimental value the value of a thing to a particular person because of its associations.

Derivative:
sentimentalism n. sentimentalist n. sentimentality n. sentimentalize v.intr. & tr. (also -ise). sentimentalization n. sentimentally adv.

N  sensibility, sensibleness, sensitiveness, moral sensibility, impressibility, affectibility, susceptibleness, susceptibility, susceptivity, mobility, vivacity, vivaciousness, tenderness, softness, sentimental, sentimentality, sentimentalism, excitability, fastidiousness, physical sensibility, sore point, sore place, where the shoe pinches, sensible, sensitive, impressible, impressionable, susceptive, susceptible, alive to, impassionable, gushing, warm hearted, tender hearted, soft hearted, tender as a chicken, soft, sentimental, romantic, enthusiastic, highflying, spirited, mettlesome, vivacious, lively, expressive, mobile, tremblingly alive, excitable, oversensitive, without skin, thin-skinned, fastidious, sensibly, to the quick, to the inmost core, mens aequa in arduis, pour salt in the wound, sensibility, sensibleness, sensitiveness, moral sensibility, impressibility, affectibility, susceptibleness, susceptibility, susceptivity, mobility, vivacity, vivaciousness, tenderness, softness, sentimental, sentimentality, sentimentalism, excitability, fastidiousness, physical sensibility, sore point, sore place, where the shoe pinches, sensible, sensitive, impressible, impressionable, susceptive, susceptible, alive to, impassionable, gushing, warm hearted, tender hearted, soft hearted, tender as a chicken, soft, sentimental, romantic, enthusiastic, highflying, spirited, mettlesome, vivacious, lively, expressive, mobile, tremblingly alive, excitable, oversensitive, without skin, thin-skinned, fastidious, sensibly, to the quick, to the inmost core, mens aequa in arduis, pour salt in the wound.

N  affectation, affectedness, acting a part, pretense boasting, charlatanism, quackery, shallow profundity, pretension, airs, pedantry, purism, precisianism, euphuism, teratology, mannerism, simagree, grimace, conceit, foppery, dandyism, man millinery, coxcombry, puppyism, stiffness, formality, buckram, prudery, demureness, coquetry, mock modesty, minauderie, sentimentalism, mauvais honte, false shame, affector, performer, actor, pedant, pedagogue, doctrinaire, purist, euphuist, mannerist, grimacier, lump of affectation, precieuse ridicule, bas bleu, blue stocking, poetaster, prig, charlatan, petit maitre, flatterer, coquette, prude, puritan, affected, full of affectation, pretentious, pedantic, stilted, stagy, theatrical, big-sounding, ad captandum, canting, insincere, not natural, unnatural, self-conscious, maniere, artificial, overwrought, overdone, overacted, euphuist, stiff, starch, formal, prim, smug, demure, tire a quatre epingles, quakerish, puritanical, prudish, pragmatical, priggish, conceited, coxcomical, foppish, dandified, finical, finikin, mincing, simpering, namby-pamby, sentimental, conceit in weakest bodies strongest works.