If you refer to someone or the way they speak as monosyllabic, you mean that they say very little, usually because they do not want to have a conversation.
He could be gruff and monosyllabic.
monosyllabic in British English
(ˌmɒnəsɪˈlæbɪk)
adjective
1.
(of a word) containing only one syllable
2.
characterized by monosyllables; curt
a monosyllabic answer
Derived forms
monosyllabically (ˌmonosylˈlabically)
adverb
monosyllabic in American English
(ˌmɑnoʊsɪˈlæbɪk; ˌ mɑnəsɪˈlæbɪk)
adjective
1.
having only one syllable
a monosyllabic word
2.
consisting of monosyllables
3.
using, or speaking in, monosyllables, often so as to seem terse or uncommunicative
Derived forms
monosyllabically (ˌmonosylˈlabically)
adverb
Word origin
ML monosyllabicus
Examples of 'monosyllabic' in a sentence
monosyllabic
The intercom gave only a monosyllabic grunt.
Len Deighton Bomber
Speaking clearly and confidently in sentences rather than monosyllabic grunts makes an enormous difference.
Times, Sunday Times (2007)
They replied to his questions with monosyllabic, embarrassed answers.
John Foot Calcio: A History of Italian Football (2006)
Show your personality, be engaging and avoid monosyllabic answers.
The Sun (2015)
He could be slow, gruff and monosyllabic.
Times, Sunday Times (2011)
He gives monosyllabic answers to the simplest of questions in a vain attempt to close down any area of questioning about his public life.
The Sun (2010)
I chat away, only to be met with monosyllabic answers.
Times, Sunday Times (2013)
Giving pretentious or monosyllabic answers results in a very dull piece of TV.