different between iff vs eff

English

Pronunciation

• Read as “if and only if”

Conjunction

iff

1. (mathematics, logic) If and only if; used to show that the truth values of two statements are the same.
2. (mathematics, logic) logically equivalent to rephrases:

   A rectangle is a square iff all four of its sides have the same length.

   1. biconditionally
   2. just in case or just in the case that
   3. equal
   4. that is to say
   5. XNOR
3. Obsolete spelling of if.

Related terms

• if
• implies
• not
• and
• or
• xor
• nand
• nor

See also

• formal logic

Translations

Anagrams

• FFI, FIF, Fif.

English

Etymology 1

A phonetic spelling of the letter f (normally spelled ef), the initial letter of the vulgar term fuck. Compare pee.

Alternative forms

• ef

Pronunciation

• enPR: ?f, IPA^(key): /?f/
• Rhymes: -?f

Verb

eff (third-person singular simple present effs, present participle effing, simple past and past participle effed)

1. (euphemistic, slang) Fuck (the taboo swear word, but not in the sense "to copulate")

Synonyms

• feck, frak, frig; see also Thesaurus:copulate or Thesaurus:copulate with

Derived terms

• eff all
• eff and blind
• effing
• eff off

Etymology 2

Back-formation from ineffable

Pronunciation

• enPR: ?f, IPA^(key): /?f/
• Rhymes: -?f

Verb

eff (third-person singular simple present effs, present participle effing, simple past and past participle effed)

1. (neologism) To put into words; to express.

Estonian

Noun

eff (genitive [please provide], partitive [please provide])

1. The name of the Latin-script letter F.

Faroese

Noun

eff n (genitive singular efs, plural eff)

1. The name of the Latin-script letter F.

Declension

See also

• (Latin-script letter names) bókstavur; a / fyrra a, á, be, de, edd, e, eff, ge, há, i / fyrra i, í / fyrra í, jodd, ká, ell, emm, enn, o, ó, pe, err, ess, te, u, ú, ve, seinna i, seinna í, seinna a, ø

Hungarian

Pronunciation

• IPA^(key): [??f?]
• Rhymes: -?f?

Noun

eff

1. The name of the Latin-script letter F.

Declension

See also

• (Latin-script letter names) bet?; a, á, bé, cé, csé, dé, dzé, dzsé, e, é, eff, gé, gyé, há, i, í, jé, ká, ell, ellipszilon / ejj, emm, enn, enny, o, ó, ö, ?, pé, kú, err, ess, essz, té, tyé, u, ú, ü, ?, vé, dupla vé / vevé, iksz, ipszilon, zé, zsé. (See also: Latin script letters.)

Further reading

• eff in Ittzés, Nóra (ed.). A magyar nyelv nagyszótára (’A Comprehensive Dictionary of the Hungarian Language’). Budapest: Akadémiai Kiadó, 2006–2031 (work in progress; published A–ez as of 2021)

Icelandic

Pronunciation

• IPA^(key): /?f?/
• Rhymes: -?f?

Noun

eff n (genitive singular effs, nominative plural eff)

1. The name of the Latin-script letter F.

Declension

Võro

Noun

eff (genitive [please provide], partitive [please provide])

1. The name of the Latin-script letter F.

Inflection

This noun needs an inflection-table template.