The meaning of fulsome is not abundantly clear

If there is a word in the English language to avoid at all costs it is fulsome. Not because it is modern (it is quite the opposite) or informal (it is not that) but because it is one of a few words that has flipped its original meaning on its head. Fulsome is even more unusual because in common usage it is returning to its original meaning. Therefore you use it at your peril.

Fulsome was originally used in Middle English (in about 1250) to mean abundant and full. This construction and meaning is quite intuitive combining full with some.

Fulsome over the centuries has become a victim of its own meaning and become more and more fulsome—it has fattened up. Its meaning moved slowly from a neutral sense of abundance and fullness to mean plump and well-fed by the 1350s. It then changed slowly to mean overgrown and overfed by the 1640s. Fulsome was corpulent by the end of the 17th century and meant offensive to taste and good manners. Its sense being excessive; overdone or gross; disgusting; sickening; repulsive; and tending towards obscenity. It came to mean excessively or insincerely lavish. And that is how it stayed until recently.

Since the 1960s fulsome, in popular usage, is used in a similar way to its original sense, meaning to encompass all aspects or abundant or copious. However, the problem is that those that use fulsome in its old positive sense are considered to be doing so out of ignorance of the established meaning. Standard English users do not accept the new usage. This is not simply conservatism but a necessary avoidance of ambiguity in the use of the word.

An added difficulty, at present, in allowing acceptance of the new meaning is that there is often an ironic undertone in its use. It is impossible to tell from the context what meaning is intended.

Fulsome is frequently paired with praise. An informed reader would read fulsome praise to mean excessive or overdone praise and perhaps even toadying flattery; while innocents would read it to mean quite generous praise. William Safire (1929-2009), New York Times political journalist and language columnist wrote in 2008:

Fulsome is to ‘full‘ what noisome is to ‘noisy‘; a word that sounds the same but means something quite different. Noisome, rooted in Old French for ‘annoying,’ means ‘smelly,’ and fulsome means ‘too much.’ If you’re on the side of clarity, hold that line.

Fulsome is having a strong resurgence amongst fashion writers who use fulsome for full in a parallel construction to wholesome or handsome. Dolce & Gabbana describe actress, Monica Bellucci, who models their new lipstick collection, in their press release as having:

… famed fulsome lips, impeccable complexion and daring, expressive eyes.

Fulsome is both an example of deterioration where a word changes over time to take on negative associations and amelioration, where a word slowly takes on favourable connotations. It depends on who you ask as too which way it is going.