In the Economist of June 30th, in a story “Shaking it all up”) on the long-standing armed insurgency in Mindinao (the southernmost region of the Philippines):
This, however, failed to satisfy the aspirations of the main separatist group, the Moro Islamic Liberation Front (MILF — the insurgency is so old that its acronym predates embarrassment).
The insurgency goes back to the early 1960s (as the Moro National Liberation Front (MNLF), formally established as MILF in 1984), while the initialism (for “Mother/Mom/Mum I‘d Like to Fuck”) goes back to the early 1990s.
MILF, an acronym for “Mother/Mom/Mum I’d Like to Fuck”, is a common colloquial term generally regarded as vulgar when spelled out. It denotes a sexually attractive older female.
The term itself was first documented in Internet newsgroups during the 1990s. It was popularized by the 1999 film American Pie referring to Jennifer Coolidge’s character: ‘Stifler’s Mom’.
The concept of a MILF predates the term itself, as exemplified by Mrs. Robinson in The Graduate .
MILF spawned the counterpart DILF (Dad I’d Like to Fuck), used by young women and gay men; a genre of pornography; and a 2010 movie:
MILF is a 2010 sex comedy film by The Asylum. The film borrows elements from American Pie and Revenge of the Nerds.
After failing romantically with girls their own age, a group of nerdy male college students discover the excitement of hooking up with sexy older women, often referred to as MILFs. Lifelong best friends Brandon (Jack Cullison) and Anthony (Philip Marlott) as well as their geek/gamer friends Nate (Joseph Booton) and Ross (Ramon Camacho) succeed beyond their wildest dreams as they hook up with lady after lady. However, when Brandon falls for Anthony’s sexually active mother, the guys’ whole scheme begins to fall apart. (link)
Details on MILF the word, from Jesse Sheidlower’s The F-Word(3rd edition), where it’s glossed ‘a sexually attractive woman who is a mother or (generally) in early middle age’: first attestation in 1991, as the name of the Buffalo NY rock band milf; then in 1995, on the Usenet newsgroup alt.mag.playboy; and then in 1998, in American Pie, which spread the word into general use.
On milf the band (three guys), from a music site:
Got milf? Buffalo sure did, at least throughout a good swath of the early-to-mid ’90s (before most of us actually knew what the now infamous acronym meant). One record scribe likened the trio music to a Husker Du 45 played at 33. Though not the most spot-on description of their sound, milf dispelled a sinewy, distorto guitar sprawl with jawdroppingly tuneful sensibilities
Other bands have picked up the name. For instance, there’s MILF! The Band (Albany CA: six women).