The spelling of the word "PLCAPK" can be explained using the International Phonetic Alphabet (IPA). The first two letters, "PL," represent a voiceless bilabial stop, meaning to abruptly stop airflow using the two lips. The next letter, "C," represents a voiceless palatal stop, which involves stopping airflow using the back of the tongue against the hard palate. The following two letters, "AP," represent a voiced alveolar stop followed by a voiceless bilabial plosive. The final letter, "K," represents a voiceless velar stop using the back of the tongue at the soft palate.