A synalepha or synaloepha (icon) is the merging of two syllables into one, especially when it causes two words to be pronounced as one.

The original meaning in Greek is more general than modern usage, and also includes coalescence of vowels within a word. Similarly, synalepha most often refers to elision

Elision

Elision is the omission of one or more sounds in a word or phrase, producing a result that is easier for the speaker to pronounce...

 (as in English contraction

Contraction (grammar)

A contraction is a shortened version of the written and spoken forms of a word, syllable, or word group, created by omission of internal letters....

), but it can also refer to coalescence by other metaplasm

Metaplasm

A metaplasm is a change in the orthography of a word. Originally it referred to techniques used in Ancient Greek and Latin poetry, or processes in those languages' grammar.-Sound change:...

s: synizesis

Synizesis

Synizesis is a sound change in which two originally syllabic vowels are pronounced as a single syllable without change in writing. In Latin and Greek, this was often to preserve meter, but similar changes occur naturally in languages....

, synaeresis

Synaeresis

In linguistics, synaeresis or syneresis is a sound change by which two vowels are pronounced together rather than separately...

, or crasis

Crasis

Crasis is a type of contraction in which two vowels or diphthongs merge into one new vowel or diphthong — making one word out of two. Crasis occurs in Portuguese and Arabic as well as in Ancient Greek, where it was first described.-French:...

.

Examples

Spanish and Italian use synalepha very frequently in poetry. As for instance in this hendecasyllable

Hendecasyllable

The hendecasyllable is a line of eleven syllables, used in Ancient Greek and Latin quantitative verse as well as in medieval and modern European poetry.-In quantitative verse:...

 (11-syllable line) by Garcilaso de la Vega

Garcilaso de la Vega

Garcilaso de la Vega was a Spanish soldier and poet. He was the most influential poet to introduce Italian Renaissance verse forms, poetic techniques and themes to Spain.-Biography:...

:

• Los cabellos que al oro oscurecían.
• "The hair that endarkened the gold"

The words que and al form one syllable when counting them because of the synalepha. The same thing happens with -ro and os-, so that the line has eleven syllables (syllable boundaries shown by a period):

• .Los.ca.be.llos.quea.lo.roos.cu.re.cí.an.

See also

• Metaplasm
  Metaplasm
  A metaplasm is a change in the orthography of a word. Originally it referred to techniques used in Ancient Greek and Latin poetry, or processes in those languages' grammar.-Sound change:...
  
  
  • Elision
    Elision
    Elision is the omission of one or more sounds in a word or phrase, producing a result that is easier for the speaker to pronounce...
    
     — Contraction (grammar)
    Contraction (grammar)
    A contraction is a shortened version of the written and spoken forms of a word, syllable, or word group, created by omission of internal letters....
    
    
    • Apharesis (initial)
    • Syncope (medial)
    • Apocope
      Apocope
      In phonology, apocope is the loss of one or more sounds from the end of a word, and especially the loss of an unstressed vowel.-Historical sound change:...
      
       (final)
  • Crasis
    Crasis
    Crasis is a type of contraction in which two vowels or diphthongs merge into one new vowel or diphthong — making one word out of two. Crasis occurs in Portuguese and Arabic as well as in Ancient Greek, where it was first described.-French:...
    
    
  • Synizesis
    Synizesis
    Synizesis is a sound change in which two originally syllabic vowels are pronounced as a single syllable without change in writing. In Latin and Greek, this was often to preserve meter, but similar changes occur naturally in languages....
    
     (merge into one syllable without change in writing)
  • Synaeresis
    Synaeresis
    In linguistics, synaeresis or syneresis is a sound change by which two vowels are pronounced together rather than separately...
    
     — opposite Diaeresis
    Diaeresis
    Diaeresis or dieresis may refer to:* Diaeresis , pronunciation of vowels in a diphthong separately, or the division made in a line of poetry when the end of a foot coincides with the end of a word...