About a word "smug"

I appreciate your fantastic supports as always.

When reading a text, I encountered this word:

complacency

And its synonyms are lined up as

self-satisfaction, smug.

Since I didn't know the word "smug", I looked it up the dictionary and found the following definitions:

It seems to me the definition 2 and definition 3 are contradictory. Or does definition 2, where it says "giving an impression", means "giving deceptive" impression (though the quote by W.W. Jacobs below does not seem so at all)?

For further additional info, according to Merriam-Webster Unabridged, "scrupulous" means.

Thank you.

Merriam-Webster's Eleventh Collegiate Dictionary (2003) gives three shorter but similar—and in this case quite helpful—definitions of smug:

smug adj. smugger; smuggest {prob[ably] mod[ification] of L[ower] G[erman] smuck neat, fr[om] M[idle] L[ow] G[erman] smucken to dress; akin to O[ld] E[nglish] smoc smock} (1551) 1 : trim or smart in dress : SPRUCE 2 : scrupulously clean, neat, or correct : TIDY 3 : highly self-satisfied

So we have a word that emerged in English around 1550 with a sense akin to "dapper" but later acquired a second meaning that emphasized scrupulous (that is, very careful) neatness. After that, again at an unspecified date, came a somewhat bigger jump to a third meaning, "self-satisfied."

Today, the vast majority of instances of smug in English use the word in this third sense—it is not a term of admiration. You are certainly correct that dictionaries normally indicate outdated meanings with labels such as "rare" or "obsolete"—but Merriam-Webster is far less inclined to assign such labels these days than it was before 1961 (when it published the Third New International Dictionary). It may be worth noting that if the usage remains current in some part of the English-speaking world, a dictionary may take the view that it is still Standard English in that sense.

On the other hand, if you had consulted The American Heritage Dictionary of the English Language, fifth edition (2011), you would have found a single definition listed in its entry for smug:

smug adj. smugger, smuggest Exhibiting or feeling great or offensive satisfaction with oneself or with one's situation; self-righteously complacent: a smug look; a smug critic. {Perhaps akin to Low German smuck, neat < Middle Low German < smucken, to adorn}

Clearly, AHDEL takes the position that only one meaning of smug is in current use in English: the meaning corresponding to definition 3 in Merriam-Webster. These are the kinds of things on which lexicographers can disagree, but in my opinion AHDEL is a more accurate source than Merriam-Webster for the meaning of smug as used today.

For historical perspective, I checked Webster's Collegiate Dictionary, fourth edition (1931). It shows the word smug at an interesting transitional phase in its contemporaneous meaning:

smug, a. SMUGGER; -GEST Primly or affectedly neat, nice, or proper, as in dress; characterized by, or of or pert[aining] to a commonplace, self-satisfied, and affectedly or primly proper air or character.

It seems to me that the crucial element in the transition from Merriam-Webster's definition 2 to MW's definition 3 is the air of primness or hyper-correctness undergirding the self-satisfaction. In more-recent decades, I believe, smug has lost much of that element of punctilious or overexact propriety; instead, the word as used today emphasizes a self-satisfaction that verges on gloating.

As I read it, your basic question is "are the two definitions contradictory?" As "smug" is commonly used today, it has a negative connotation. In general, one would not be pleased to be described as "smug," to this extent smugness is similar to hubris, "overbearing pride or presumption." On the face of it, the second (which doesn't seem negative) and third (which does seem negative) definitions are contradictory. But then you have the phrase "giving the impression," which to me means the person described is actively projecting his correctness and respectability, which is boasting and definitely has a negative connotation. So, if the definition were simply "correctness and respectability," the contradiction would be undeniable, but "impressing" one's C&R on the world brings it so close to definition three, that the contradiction fades.