Not ridiculous, as an argument

• Like a sound argument
• Like a rational argument
• Possible to defend
• Logical, as a theory (7)
• Solidly based
• Seemingly rational little gap in record
• Like some arguments
• Like a well-armed fort

WordNet Word definitions in WordNet
adj. based on sound reasoning or evidence; "a reasonable argument"; "well-founded suspicions" [syn: well-founded ]

Wikipedia Word definitions in Wikipedia