What are the bedside pinyin syllables in pinyin light syllables?

The multivariate input method (multivariate Chinese character and graphic symbol input method) enters dx in the text search column of the "General Specification Chinese Character Multivariate Code Table", and types the word "head", which is known to have an explanation on page 1311 of the 6th edition of the "Modern Chinese Dictionary":

Head] tou noun suffix. Direction word suffix.

【bedhead】can be pinyin as chiáng tou. But the pinyin of [bedside table] is chiángtóuguì (the "head" here is not a suffix).