Aim: This study aimed to identify paediatric terminology used in the Australian health and health‐education context, propose a standardized framework for Australian use, and compare it with a US‐based framework.

Method: Australian health and health‐education websites were systematically searched using a novel hierarchical domain‐specific search strategy to identify grey literature containing paediatric terminology. Webpages published from 2009 to February 2014, with a ‘.gov.au’ or ‘.edu.au’ domain and no advertising, were included. Paediatric terms were analysed with power‐law distributions. Age definitions were grouped using a chi‐squared test automatic interaction detection analysis (p<0.05).

Results: In total, 34 paediatric terms and 197 unique age definitions were identified in 613 webpages. Terms displayed a language distribution, although definitions had semantic and lexical ambiguity. Age definitions were divided into four statistically different groups (F=245.3, p<0.001). Four paediatric terms with distinct age definitions were proposed based on Australian data: ‘infant: 0 to <1 year’, ‘early childhood: 1 year to <5 years’, ‘child: 5 years to <13 years’, and ‘young person: 13 years to <22 years’. These recommendations were broader than the US‐based comparison.