We found 15 dictionaries that define the word sickliness:

General (12 matching dictionaries)

1. sickliness: Merriam-Webster
2. sickliness: Oxford Learner's Dictionaries
3. sickliness: Collins English Dictionary
4. sickliness: Wordnik
5. sickliness: Wiktionary
6. sickliness: Dictionary.com
7. Sickliness: Online Plain Text English Dictionary
8. sickliness: Webster's Revised Unabridged, 1913 Edition
9. Sickliness: AllWords.com Multi-Lingual Dictionary
10. sickliness: Webster's 1828 Dictionary
11. sickliness: FreeDictionary.org
12. sickliness: TheFreeDictionary.com

Business (1 matching dictionary)

13. sickliness: Legal dictionary

Computing (1 matching dictionary)

14. sickliness: Encyclopedia

Medicine (1 matching dictionary)

15. sickliness: Merriam-Webster Medical Dictionary

(Note: See sickly as well.)

Definitions from Wiktionary (sickliness) ▸ noun:  The state or characteristic of weakness, incapacity, or physical distress due to poor health, especially of a chronic nature. Similar: sickishness, mislike, sickness, unwellness, diseasedness, debility, poorliness, sickerness, weakishness, weakliness, more... Opposite: healthiness, robustness, vitality, wellness ▸ Words similar to sickliness ▸ Usage examples for sickliness ▸ Idioms related to sickliness ▸ Wikipedia articles (New!) ▸ Popular adjectives describing sickliness ▸ Words that often appear near sickliness ▸ Rhymes of sickliness ▸ Invented words related to sickliness