Sign space

The grammar of American Sign Language (ASL) is the best studied of any sign language, though research is still in its infancy, dating back only to William Stokoe in the 1960s.

ASL morphology is to a large extent iconic. This shows up especially well in reduplication and indexicality.

Compounding is used to derive new words in ASL, which often differ in meaning from their constituent signs. For example, the signs FACE and STRONG compound to create a new sign FACE^STRONG, meaning 'to resemble'. Compounds undergo the phonetic process of "hold deletion", whereby the holds at the end of the first constituent and the beginning of the second are elided:

Many ASL nouns are derived from verbs. This may be done either by reduplicating the movement of the verb if the verb has a single movement, or by restraining (making smaller and faster) the movement of the verb if it already has repeated movement. For example, the noun CHAIR is derived from the verb SIT through reduplication. Another productive method is available for deriving nouns from non-stative verbs. This form of derivation modifies the verb's movement, reduplicating it in a "trilled" manner ("small, quick, stiff movements"). For example, this method is used to derive the noun ACTION from the verb ACT.

Characteristic adjectives, which refer to inherent states, may be derived from adjectives which refer to "incidental or temporary states". Characteristic adjectives always use both hands, even if the source adjective only uses one, and they always have repeated, circular movement. Additionally, if the source adjective was one-handed, the derived adjective has alternating movement. "Trilling" may also be used productively to derive adjectives with an "ish" meaning, e.g. BLUE becomes BLUISH.

ASL occasionally uses suffixation in derivation, but less often than in English. Agent nouns may be derived from verbs by adding the suffix AGENT and deleting the final hold of the verb, e.g. TEACH+AGENT 'teacher'. Superlatives are also formed by suffixation, e.g. SMART+MOST 'smartest'.

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