Not compact; not having the parts firmly united; incoherent or loose.
Not too heavy for an intended purpose.
Being less invested in a particular area than market wisdom suggests.
Of an inappropriately or unusually low weight.
The state or quality of being underweight.
An underweight person.
An underweight investment.
To underestimate the weight of.
To give insufficient weight to (a consideration); to underestimate the importance of.
To invest in less than conventional wisdom would dictate.