ðə tˈɜːm kˈʌmz fɹʌm spˈænɪʃ kˈæmɪsə ʃˈɜːt: wˌɛn ðə tˈɜːsɪˌoʊ hæd ˈækʃənz skˈɜːmɪʃᵻz ʌv ɚɹˈaʊnd fˈɪfti mˈɛn ɐtˈækɪŋ æt nˈaɪt wɪð mˈɪnɪməm ɪkwˈɪpmənt, ˈoʊnli sˈoːɹd ænd dˈæɡɚ ɔːlðˈoʊ sˌʌm sˈoʊldʒɚz kʊd kˈæɹi ˈɑːɹkwɛbəs ɔːɹ mˈʌskɪt, ænd ðeɪ wɜː dɹˈɛst ˈoʊnli wɪð ɐ wˈaɪt ʃˈɜːt ðˈʌs ðə spˈænɪʃ wˈɜːd :ˈiːz:ɛŋkˌæmɪsˈɑːdə, ɪn ˈɔːɹdɚ tə kˈɪl ɪn sˈaɪləns æz mˈɛni ˈɛnəmiz æz pˈɑːsᵻbəl wˌaɪl ðeɪ wɜː slˈiːpɪŋ.
The term comes from Spanish camisa (shirt): when the Tercio had actions (skirmishes) of around fifty men attacking at night with minimum equipment, only sword and dagger (although some soldiers could carry arquebus or musket), and they were dressed only with a white shirt (thus the Spanish word :es:encamisada), in order to kill in silence as many enemies as possible while they were sleeping.