A literal use (haqiqah) employs a word in its established meaning; a figurative use (majaz) extends it by an intelligible relationship and indication. Custom may determine the operative usage so firmly that a remote dictionary possibility is not decisive.
For example, an oath mentioning a “head” or “foot” must be interpreted by the prevailing usage and subject of the speech. Every theoretical dictionary meaning does not produce the same legal result.
Analytical sequence
1. Identify the literal meaning and whether it can operate.
2. Examine ordinary or specialized custom.
3. Identify a reliable indicator for figurative use.
4. Determine the resulting effect on an oath, acknowledgement or contract.
An impossible, abandoned and still-used literal meaning do not have identical interpretive force.